Computer Supported Cooperative Work 11: 411–446, 2002.
© 2002 Kluwer Academic Publishers. Printed in the Netherlands. 411
A Descriptive Framework of Workspace Awareness
for Real-Time Groupware
CARL GUTWIN1& SAUL GREENBERG2
1Department of Computer Science, University of Saskatchewan, 57 Campus Drive, Saskatoon,
Canada, S7N 5A9 (E-mail: email@example.com); 2Department of Computer Science, University of
Calgary, 2500 University Drive NW, Calgary, Canada, T2N 1N4 (E-mail: firstname.lastname@example.org)
Abstract. Supporting awareness of others is an idea that holds promise for improving the usability
of real-time distributed groupware. However, there is little principled information available about
awareness that can be used by groupware designers. In this article, we develop a descriptive theory
of awareness for the purpose of aiding groupware design, focusing on one kind of group awareness
called workspace awareness. We focus on how small groups perform generation and execution
tasks in medium-sized shared workspaces – tasks where group members frequently shift between
individual and shared activities during the work session. We have built a three-part framework that
examines the concept of workspace awareness and that helps designers understand the concept
for purposes of designing awareness support in groupware. The framework sets out elements of
knowledge that make up workspace awareness, perceptual mechanisms used to maintain awareness,
and the ways that people use workspace awareness in collaboration. The framework also organizes
previous research on awareness and extends it to provide designers with a vocabulary and a set of
ground rules for analysing work situations, for comparing awareness devices, and for explaining
evaluation results. The basic structure of the theory can be used to describe other kinds of awareness
that are important to the usability of groupware.
Key words: awareness, groupware design, groupware usability, real-time distributed groupware,
situation awareness, shared workspaces, workspace awareness
Awareness has recently begun to receive considerable attention in CSCW and
groupware research (e.g. Dourish and Bellotti, 1992; McDaniel and Brinck, 1997;
Rodden, 1996; Gutwin and Greenberg, 1998a). While staying aware of others is
something that we take for granted in the everyday world, maintaining this aware-
ness has proven to be difﬁcult in real-time distributed systems where information
resources are poor and interaction mechanisms are foreign. As a result, working
together through a groupware system often seems inefﬁcient and clumsy compared
with face-to-face work. It is becoming more and more apparent that being able to
stay aware of others plays an important role in the ﬂuidity and naturalness of collab-
oration, and supporting awareness of others is looked on as one way of reducing the
characteristic awkwardness of remote collaboration. Awareness is a design concept
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412 CARL GUTWIN & SAUL GREENBERG
that holds promise for signiﬁcantly improving the usability of real-time distributed
Despite this attention, no clear overall picture of awareness has yet emerged
from the CSCW community. With a few exceptions, awareness support presented
to date involves localized solutions to speciﬁc domain problems, and isolated
approaches and principles that are difﬁcult to generalize to other situations. Most
importantly, this void means that groupware designers have little principled infor-
mation available to them about how to support awareness in other domains and
new systems. Faced with a blank slate for each new application, designers must
reinvent awareness from their own experience of what it is, how it works, and how
it is used in the task at hand.
Our goal in this article is to develop a descriptive theory of awareness for the
purpose of aiding groupware design. We synthesize and organize existing research
on awareness, and extend this work through a conceptual framework. Our motiva-
tion is the observation that current groupware systems are not particularly usable
– and here we are more concerned with how well a system supports activities of
collaboration like communication, coordination, and assistance, than we are with
how well the system supports the domain task (Salas, 1995). Our overall research
hypothesis is that helping people to stay aware in groupware workspaces will
improve a groupware system’s usability.
Our conceptual framework differs from previous work on groupware awareness
in three ways:
•it integrates and expands upon a variety of observations and previous theories
•it addresses a particular type of situation – small groups working over medium
sized shared workspaces; and
•it is intended to assist the iterative design of real-time distributed groupware.
We examine one kind of awareness in collaboration – called workspace aware-
ness because of its intimate relationship with shared workspaces – and construct
a framework that describes the concept for use in groupware design. Workspace
awareness is the up-to-the-moment understanding of another person’s interaction
with a shared workspace (Gutwin and Greenberg, 1996). Workspace awareness
(WA) involves knowledge about where others are working, what they are doing,
and what they are going to do next. This information is useful for many of the
activities of collaboration – for coordinating action, managing coupling, talking
about the task, anticipating others’ actions, and ﬁnding opportunities to assist one
Starting from recent human factors research on awareness and from Neisser’s
(1976) cognitive model of how awareness is maintained, our WA framework is
organized around three issues:
•what kinds of information people keep track of in shared workspaces;
•how people gather workspace awareness information; and
•how people use workspace awareness information in collaboration.
REAL-TIME GROUPWARE 413
These three areas inform three problems faced by groupware designers setting out
to support awareness: what information to gather and distribute, how to present
the information to the group, and when the information will be most useful. The
framework provides designers with a structure to organize thinking about aware-
ness support, a vocabulary for analysing collaborative activity and for comparing
solutions, and a set of starting points for more speciﬁc design work. We do not give
prescriptive rules and guidelines, however, since each groupware application will
have to operate within particular awareness requirements dictated by the task and
the group situation.
The framework was developed iteratively over several years (e.g. see Gutwin
and Greenberg, 1996; Gutwin, Greenberg, and Roseman, 1996; Gutwin and
Greenberg, 1998a) and is derived from a variety of sources:
•observations and insights of other groupware developers on issues concerning
awareness (e.g. Steﬁk et al., 1987a; Tang, 1991; Beaudouin-Lafon and
Karsenty, 1992; Dourish and Bellotti, 1992; Dix et al., 1993);
•theories developed by psychologists, linguists, ethnographers and human
factors researchers on awareness (e.g., Clark, 1996; Brennan, 1990; Heath
and Luff, 1995; Endsley, 1995);
•our own observational studies of face to face groups performing tasks over
shared work surfaces (see Appendix A);
•our own iterative development and testing of many awareness widgets and
displays, where we analyzed reasons for success and failure (e.g. Gutwin and
Greenberg, 1996b, 1998a).
In this article, we explore workspace awareness and detail the three parts of the
conceptual framework. To begin, we outline the concepts that underlie and bound
the research, such as real-time distributed groupware, shared workspaces, and
workspace awareness. Next, we give more detail on why awareness is a problem
in groupware, and on the difﬁculty of supporting workspace awareness in a distrib-
uted computational setting. Third, we discuss human factors research into what
awareness is and how it works, research that underlies the conceptual framework.
We then introduce the three-part framework itself.
2. Setting the scene
There are bounds on the collaborative situations that we consider in this research.
Our boundaries involve the kinds of groups we are trying to support, the workspace
environment where collaboration takes place, the kinds of tasks that groups will
undertake, and the kinds of groupware that will be used.
Systems: Real-time distributed groupware. Real-time distributed group-
ware systems allow people to work or play together at the same time, but from
different places (e.g. Ellis et al., 1991). Although many kinds of group activity
can be supported with real-time distributed groupware, we are particularly
interested in applications that provide a shared workspace.
414 CARL GUTWIN & SAUL GREENBERG
Environment: Shared workspaces. Many real-time groupware systems
provide a bounded space where people can see and manipulate artifacts related
to their activities. We concentrate on ﬂat, medium-sized surfaces upon which
objects can be placed and manipulated, and around which a small group
of people can collaborate. In these spaces, the focus of the activity is on
the visible and manipulable objects through which the task is carried out.
The combination of physical space and artifacts makes a shared workspace
an external representation of the joint activity (Clark, 1996; Norman, 1993;
Tasks: Generation and execution. Primary task types in shared work-
spaces are generation and execution activities (McGrath, 1984). In particular,
these tasks tend to involve creation of new artifacts, navigation through a
space of objects, or performance of physical manipulation on existing arti-
facts. Examples include activities such as construction (page layout, diagram
assembly), organization (arranging, ordering, or sorting artifacts), design
(drawing, generating an outline), or exploration (ﬁnding certain types of arti-
facts in the space). Other types of tasks (e.g. decision-making) also involve
workspace awareness, but as these types involve less interaction with the
artifacts, we do not consider them as primary for the framework.
Groups: Small groups and mixed-focus collaboration. Small groups of
between two and ﬁve people primarily carry out tasks in these medium-sized
workspaces. These groups often engage in mixed-focus collaboration, where
people shift frequently between individual and shared activities during a work
session (e.g. Dourish and Bellotti, 1992; Salvador et al., 1995). Although
larger groups may also engage in tasks that require workspace awareness, it is
less common for large groups to work synchronously over a shared workspace
(because of space limitations), and we take small group activity as our primary
Within these boundaries, a rich variety of small-group collaboration is possible.
For example, typical examples might include two people organizing slides on a
light table, a research group generating ideas on a whiteboard, or the managers of a
project planning a task timeline. These and all the other group activities within our
boundaries share a common problem when they take place in a groupware setting:
it is difﬁcult to maintain awareness of others in the workspace.
3. The awareness problem in groupware workspaces
In a face-to-face workspace, awareness of one another is relatively easy to main-
tain, and the mechanics of collaboration are natural, spontaneous, and unforced.
Unfortunately, workspace awareness is much harder to maintain in groupware
workspaces than in face-to-face environments, and it is often difﬁcult or impossible
to determine who else is in the workspace, where they are working, and what they
REAL-TIME GROUPWARE 415
Figure 1. GroupSketchpad, a relaxed-WYSIWIS shared whiteboard.
There are three main reasons why this is so. First, the input and output devices
used in groupware systems generate only a fraction of the perceptual information
that is available in a face-to-face workspace. Second, a user’s interaction with a
computational workspace generates much less information than actions in a phys-
ical workspace. Third, groupware systems often do not present even the limited
awareness information that is available to the system.
As an example, consider a basic shared whiteboard such as the GroupSketchpad
system from the GroupKit toolkit (Roseman and Greenberg, 1995), seen in
Figure 1. As each person draws, their actions are communicated to the other
machine, so both participants’ workspaces contain the same objects. At this
moment in their task, the participants have scrolled their viewports to different
parts of the workspace, and only a portion of their views overlap.
Systems like this one show almost none of the awareness information that would
be available to a group working with a physical whiteboard. People’s hands and
bodies are reduced to simple telepointers, there is no sound, and only a small piece
of the entire drawing can be seen at one time. In this situation, it will be difﬁcult
or impossible for the two participants to discuss particular objects, provide timely
assistance, monitor the other person’s activities, or anticipate their actions. In short,
lack of information about others means that many of the little things that contribute
to smooth and natural collaboration will be missing from the interaction.
In relaxed-WYSIWIS systems like this one, the awareness problem is particu-
larly severe. When different people can scroll to different parts of the workspace
(as in mixed-focus collaboration), they still need to maintain awareness of others;
however, any information about where the other person is working or what they are
doing can only be gathered through verbal communication. Once a person loses
track of their partner, collaborating with them in real time becomes much more
416 CARL GUTWIN & SAUL GREENBERG
How can groupware designers address the awareness problem? Part of the solu-
tion is to provide people with more information about their collaborators. As it
is infeasible to replicate the detail and size of real-world workspaces, however,
designers must carefully determine what information is most important, and how it
can be put to best advantage in the system. The framework of workspace awareness
is intended to provide designers with assistance in making these decisions. The
ﬁrst step involves setting out more precisely what workspace awareness is, and the
process by which people manage to maintain it.
In this section, we outline characteristics of awareness that are relevant to group
work, describe prior research in awareness, describe the concept of workspace
awareness in more detail, and set out a model of how awareness is maintained.
4.1. CHARACTERISTICS OF AWARENESS
Previous researchers have deﬁned awareness as knowledge created through inter-
action between an agent and its environment – in simple terms, “knowing what
is going on” (Endsley, 1995, p. 36). This conception of awareness involves states
of knowledge as well as dynamic processes of perception and action. Four basic
characteristics run through prior work on awareness (e.g. Adams et al., 1995;
Norman, 1993; Endsley, 1995).
1. Awareness is knowledge about the state of an environment bounded in time
2. Environments change over time, so awareness is knowledge that must be
maintained and kept up to date.
3. People interact with and explore the environment, and the maintenance of
awareness is accomplished through this interaction.
4. Awareness is a secondary goal in the task – that is, the overall goal is not simply
to maintain awareness but to complete some task in the environment.
Everyone has experienced this kind of awareness; at its most basic, it is what
allows us to walk around without bumping into things. As situations and environ-
ments become more complex, however, information demands sometimes outstrip
our ability to attend, and awareness becomes more noticeable. In these contexts,
previous researchers have explored what they call situation awareness, a concept
that underlies the idea of workspace awareness in groupware.
4.2. SITUATION AWARENESS (SA)
Research into awareness as we describe it above originated in the study of military
aviation, where pilots interact with highly dynamic, information-rich environ-
ments. In recent years, researchers have expanded their focus to other environments
REAL-TIME GROUPWARE 417
where situation awareness plays a major role, such as commercial aviation (Sarter
and Woods, 1995), air trafﬁc control (Smith and Hancock, 1995), and anesthesi-
ology (Gaba and Howard, 1995). These environments all share the characteristics
of “dynamism, complexity, high information load, variable workload, and risk”
(Gaba and Howard, 1995).
The human factors community has not settled on a single deﬁnition of situation
awareness, but most researchers include aspects of product (i.e. knowledge that an
actor can make use of), and process (i.e. how that knowledge is created through
interaction with the environment). A good general deﬁnition of SA is as “the up-
to-the minute cognizance required to operate or maintain a system” (Adams et al.,
1995, p. 85). Endsley (1995) focuses more on the process, proposing a three stage
Level 1: perception of relevant elements of the environment. An actor must
ﬁrst be able to gather perceptual information from the environment, and be
able to selectively attend to those elements that are most relevant for the task
Level 2: comprehension of those elements. An actor must be able to inte-
grate the incoming perceptual information with existing knowledge, and make
sense of the information in light of the current situation.
Level 3: prediction of the states of those elements in the near future.To
perform well in a situation, an actor must also be able to anticipate changes
to the environment and be able to predict how incoming information will
The characteristics of awareness as introduced above also apply to workspace
awareness: it is knowledge of a dynamic environment, it is maintained through
perceptual information gathered from the environment, and it is peripheral to
the primary group activity. We view workspace awareness as a specialization of
situation awareness, one that is tied to the speciﬁc setting of the shared workspace.
4.3. WORKSPACE AWARENESS
We deﬁne workspace awareness as the up-to-the-moment understanding of another
person’s interaction with the shared workspace. This deﬁnition bounds the concept
in two ways. First, workspace awareness is awareness of people and how they
interact with the workspace, rather than just awareness of the workspace itself.
Second, workspace awareness is limited to events happening in the workspace –
inside the temporal and physical bounds of the task that the group is carrying
out. This means that workspace awareness differs from informal awareness of
who is around and available for collaboration, and from awareness of cues and
turns in verbal conversation, both of which have been studied previously in CSCW
(e.g. Borning and Travers, 1991; Dourish and Bly, 1992; Greenberg, 1996) and in
linguistics (e.g. Clark, 1996; Goodwin, 1981).
418 CARL GUTWIN & SAUL GREENBERG
Figure 2. Domain and collaboration tasks.
The shared workspace setting makes workspace awareness a specialized kind
of situation awareness. When someone works alone in a workspace, their activities
and their SA involve only the workspace and the domain task (see Figure 2). In
a collaborative situation, however, people must undertake another task, that of
collaboration, and therefore their situation awareness must involve both the domain
and the collaboration.
A second apparent difference between workspace awareness and situation
awareness is that collaborating in most shared workspaces often does not involve
high information load or extreme dynamism.1That is, it is not generally difﬁcult
to maintain workspace awareness in the real world: sorting slides on a table does
not seem very similar to air combat in a jet ﬁghter. However, the two types of
situations do share an important characteristic, : that people are unable to gather the
information that they need from the environment. In the jet aircraft, the information
load exceeds the pilot’s ability to take it all in. In the slide-sorting task, although
the participants’ perception would normally be perfectly adequate, a groupware
system has artiﬁcially reduced their abilities to gather awareness information.
This means that the initial problems of maintaining WA in groupware revolve
around obtaining useful information, rather than around what people make of
the information. In the situations that SA research currently studies, problems
can occur at any of Endsley’s three levels: people can fail to gather important
information from the environment, they may fail to understand what that gathered
information means to the activity, or they may fail to predict what that information
means for future events. In workspace situations, all of these can also occur, but we
must focus ﬁrst on the lack of information at the ﬁrst and second levels. People’s
perception is artiﬁcially hampered by the technological constraints of a groupware
system: information may be unavailable, or it may be presented in a form that
makes the information unusable for maintaining up-to-the-moment awareness. The
designer’s task and our conceptual framework concentrate on these two levels: on
REAL-TIME GROUPWARE 419
Figure 3. The perception-action cycle (Neisser, 1976).
determining what information to present, and on presenting that information so that
people can maintain awareness easily and naturally.
4.4. MAINTAINING AWARENESS
Understanding how people maintain awareness is crucial if we are to design
systems that support workspace awareness. Adams et al. (1995) suggest a cognitive
model that shows how awareness is maintained in dynamic environments, a model
that also draws together the process and product aspects of different deﬁnitions
of SA. The model is Neisser’s (1976) perception-action cycle, a “cognitive frame-
work for the interdependence of memory, perception, and action” (Adams et al.,
1995, p. 88). Neisser’s model, shown in Figure 3, captures the interaction between
the agent and the environment, and incorporates relationships between a person’s
knowledge and their information-gathering activity. It differs from linear models of
information processing by recognizing that perception is inﬂuenced and directed by
Awareness of an environment is created and sustained through the perception-
action cycle. When a person enters an environment to do a particular task, they
bring with them a general understanding of the situation and a basic idea of what
to look for. The information that they then pick up from the environment can be
interpreted in light of existing knowledge to help the person determine the current
state of the environment – that is, what is happening – and also help them to predict
what will happen next. These expectations lead to a further reﬁnement in perceptual
sensitivity, as when the expectation of seeing another aircraft sensitizes a pilot to
subtle variations in the visual ﬁeld (Adams et al., 1995, p. 89). The perception-
420 CARL GUTWIN & SAUL GREENBERG
action cycle combines both product and process aspects of awareness. Product
is captured by the active knowledge created by previous cycles, and process is
captured by the movement around the cycle.
To summarize thus far, Neisser’s cycle and the research into situation awareness
provide us with a foundation for a conceptual framework of workspace awareness.
We have established that workspace awareness is a specialization of SA, where
the ‘situation’ is well-deﬁned – others’ interactions with a shared workspace.
Workspace awareness is maintained through a perception-action cycle, in which
awareness knowledge both directs, and is updated by, perceptual exploration of
the workspace environment. Finally, the initial problem in maintaining workspace
awareness in distributed settings is that groupware technology limits what people
can perceive of others in the workspace, hindering their ability to gather WA
information from the environment.
We now turn to the conceptual framework itself. Part one involves the types
of information that make up WA, Part two involves the mechanisms people use
to gather WA information, and Part three involves the ways that people use WA
information in collaboration. The contents of the framework come from existing
research in CSCW, HCI, and human factors, and from our own observations of
simple tabletop tasks and of real world group work in ofﬁces and control rooms.2
After the three sections dealing with the framework, we discuss ways in which the
knowledge of the framework can be used in the design of interface widgets and
5. Framework part one: What information makes up workspace awareness?
Workspace awareness is made up of many kinds of knowledge, and the ﬁrst part of
the framework divides the concept into components. This part of the framework
gives designers a basic idea of what information to capture and distribute in a
groupware system. Even though a person can keep track of many things in a shared
workspace, elements from a basic set make repeated appearances in research liter-
ature (e.g. Dourish and Bellotti, 1992; Sohlenkamp and Chwelos, 1994; McDaniel
and Brinck, 1997). The basic set is the elements that answer “who, what, where,
when, and how” questions. That is, when we work with others in a physical shared
space, we know who we are working with, what they are doing, where they are
working, when various events happen, and how those events occur. People keep
track of these things in all kinds of collaborative work, and these are the kinds of
information that should be considered ﬁrst by designers.
Within these basic categories, we have identiﬁed speciﬁc elements of knowl-
edge that make up the core of workspace awareness. Tables I and II show these
elements and list the questions that each element can answer. Table I contains those
elements that relate to the present, and Table II contains those that relate to the
past. The elements are all commonsense things that deal with interactions between
a person and the environment. Awareness of presence and identity is simply the
REAL-TIME GROUPWARE 421
Table I. Elements of workspace awareness relating to the present
Category Element Speciﬁc questions
Who Presence Is anyone in the workspace?
Identity Who is participating? Who is that?
Authorship Who is doing that?
What Action What are they doing?
Intention What goal is that action part of?
Artifact What object are they working on?
Where Location Where are they working?
Gaze Where are they looking?
View Where can they see?
Reach Where can they reach?
knowledge that there are others in the workspace and who they are, and authorship
involves the mapping between an action and the person carrying it out. Awareness
of actions and intentions is the understanding of what another person is doing,
either in detail or at a general level. Awareness of artifact means knowledge about
what object a person is working on. Location, gaze, and view relate to where the
person is working, where they are looking, and what they can see. Awareness of
reach involves understanding the area of the workspace where a person can change
things, since sometimes a person’s reach can exceed their view.
Awareness of the past involves several additional elements. Action and artifact
history concern the details of events that have already occurred, and event history
concerns the timing of when things happened. The remaining three elements
deal with the historical side of presence, location, and action. We do not include
elements relating to the future in our framework, because designers are unlikely to
be able to support maintenance of those elements. This is because past and present
information can be determined from raw perceptual information, whereas belief
about the future involves inference, extrapolation, and prediction.
Workspace awareness knowledge will be made up of these elements in some
combination, and participants in a face-to-face group activity will generally know
the basic elements (consciously or unconsciously). This does not mean, however,
that the designer should support all elements equally in the interface. Two factors
are critical in determining how the designer should treat each element. First, the
degree of interaction between the participants in the activity indicates how speciﬁc
or general the information in the interface should be. Second, the dynamism of the
element – how often the information changes – indicates how often the interface
will need to be updated. In some situations, certain elements never change, and so
do not require explicit support in the interface. For example, if the participants in
422 CARL GUTWIN & SAUL GREENBERG
Table II. Elements of workspace awareness relating to the past
Category Element Speciﬁc questions
How Action history How did that operation happen?
Artifact history How did this artifact come to be in this state?
When Event history When did that event happen?
Who (past) Presence history Who was here, and when?
Where (past) Location history Where has a person been?
What (past) Action history What has a person been doing?
an activity are always assigned to particular areas of the workspace, there is little
need for the system to gather and distribute location information.
Although there will also be additional kinds of information speciﬁc to the task
or the work setting, these basic elements provide a high-level organization of work-
space awareness. The elements are a starting point for thinking about the awareness
requirements of particular task situations, and provide a vocabulary for describing
and comparing awareness support in groupware applications.
6. Framework part two: How is workspace awareness information
The groupware designer must attempt to present awareness information in ways
that make the maintenance of workspace awareness simple and straightforward.
We believe that this will be easier if people can gather information in familiar ways,
even though the actual interface devices in a groupware system may not be familiar.
This means understanding the mechanisms people use to gather workspace aware-
ness information from the workspace environment – basically, how people ﬁnd the
answers to the who, what, where, when, and how questions listed in Tables I and
II. In this section, we outline some of the ways that people ﬁnd those answers.
Prior research suggests three main sources of workspace awareness information,
and three corresponding mechanisms that people use to gather it (Segal, 1994;
Norman, 1993; Dix et al., 1993; Hutchins, 1990). People obtain information that is
produced by people’s bodies in the workspace, from workspace artifacts, and from
conversations and gestures. The mechanisms that they use to gather it are called
consequential communication, feedthrough, and intentional communication.
6.1. BODIES AND CONSEQUENTIAL COMMUNICATION
The ﬁrst information source is the other person’s body in the workspace (e.g.
Segal, 1994; Norman, 1993; Benford et al., 1995). Since most things that people
REAL-TIME GROUPWARE 423
do in a workspace are done through some bodily action, the position, posture, and
movement of heads, arms, eyes, and hands provide a wealth of information about
what’s going on. Therefore, watching other people work is a primary mechanism
for gathering awareness information: “whenever activity is visible, it becomes an
essential part of the ﬂow of information fundamental for creating and sustaining
teamwork” (Segal, 1994, p. 24). Although people also contribute to the auditory
environment, much of the perception of a body in a workspace is visual. In all of
the tabletop tasks that we observed, for example, participants would regularly turn
their heads to watch their partners work.
The mechanism of seeing and hearing other people active in the workspace
is called consequential communication: information transfer that emerges as a
consequence of a person’s activity within an environment (Segal, 1994). This
kind of bodily communication, however, is not intentional in the way that explicit
gestures are: the producer of the information does not intentionally undertake
actions to inform the other person, and the perceiver merely picks up what is
available. Nevertheless, consequential communication provides a great deal of
information. In a study of piloting teams, Segal reports that:
[Pilots] spent most of their time – over 60% – looking across at their [partner’s]
display while it was being manipulated. This suggests that beyond the informa-
tion provided by the display itself, these pilots were speciﬁcally looking for
information provided by the dynamic interaction between their crewmembers
and that display. (p. 24)
This study also suggests that movement is particularly important in consequen-
tial communication, since our attention is naturally drawn to motion. Norman
(1993) gives an example, when he relates the value of “obvious actions” in aircraft
When the captain reaches across the cockpit over to the ﬁrst ofﬁcer’s side and
lowers the landing-gear lever, the motion is obvious: the ﬁrst ofﬁcer can see
it even without paying conscious attention. The motion not only controls the
landing gear, but just as important, it acts as a natural communication between
the two pilots, letting both know the action has been done. (p. 142)
6.2. ARTIFACTS AND FEEDTHROUGH
The artifacts in the workspace are a second source of awareness information
(e.g. Dix et al., 1993; Gaver, 1991). Artifacts provide several sorts of visual
information: they are physical objects, they form spatial relationships to other
objects, they contain visual symbols like words, pictures, and numbers, and their
states are often shown in their physical representation. Artifacts also contribute
to the acoustic environment, making characteristic sounds when they are created,
destroyed, moved, stacked, divided, or manipulated in other ways (Gaver, 1991).
Tools in particular have signature sounds, such as the snip of scissors or the scratch
424 CARL GUTWIN & SAUL GREENBERG
of a pencil. By seeing or hearing the ways that an artifact changes, it is often
possible to determine what is being done to it.
This mechanism is feedthrough (Dix et al., 1993): when artifacts are manipu-
lated, they give off information, and what would normally be feedback to the
person performing the action can also inform others who are watching. When
both the artifact and the actor can be seen, feedthrough is coupled with consequen-
tial communication; at other times, there may be a spatial or temporal separation
between the artifact and the actor, leaving feedthrough as the only vehicle for infor-
mation. For example, in our observations of the Calgary air trafﬁc control centre
(Appendix 1), the departures controller cannot monitor all of the arrival controller’s
actions, but can see the status of arriving aircraft on their display change from
“approaching” to “landed.” When they see this change in the artifact, they can also
infer the activities of the arrivals controller.
6.3. CONVERSATION,GESTURE,AND INTENTIONAL COMMUNICATION
A third source of information that is ubiquitous in collaboration is conversation
and gesture, and their mechanism is intentional communication (e.g. Clark, 1996;
Heath and Luff, 1995; Birdwhistell, 1952). Verbal conversations are the prevalent
form of communication in most groups, and there are three ways in which aware-
ness information can be picked up from verbal exchanges. First, people may
explicitly talk about awareness elements with their partners, and simply state where
they are working and what they are doing. Our observations of shared-workspace
tasks suggest that these direct discussions happen primarily when someone asks a
speciﬁc question such as “what are you doing?” or when the group is planning or
replanning the division of labour.
Second, people can gather awareness information by overhearing others’
conversations. Although a conversation between two people may not explicitly
include a third person, it is understood that the exchange is public information
that others can pick up. For example, navigation teams on navy ships talk on
an open circuit, which means that everyone can hear each others’ conversations.
Hutchins (1990) details how members of the team listen in on these conversations,
either to monitor the actions of a junior member, or to learn from more experi-
enced members. For this reason, voice loops – audio channels that allow directed
and overheard communication among spatially separate sub-groups of people –
have evolved as standard practice in mission control domains such as air trafﬁc
management, aircraft carrier operations, and space mission control (Watts et al.,
Third, people can pick up others’ verbal shadowing, the running commentary
that people commonly produce alongside their actions, spoken to no one in
particular. Heath and Luff (1995) have observed this behaviour, which they call
“outlouds.” They note that although these “outlouds ... might be thought relatively
incursive, potentially interrupting activities being undertaken by [others] in the
REAL-TIME GROUPWARE 425
room, [they are] perhaps less obtrusive than actually informing particular persons”
The style of verbal shadowing can be explicit or highly indirect. In the our
observations of a newspaper-layout task (Appendix 1), participants regularly stated
exactly what they were doing, saying things like “I’m going to cut this article,” or
“I’ll move this over here.” In other work situations like the London Underground
(Heath and Luff, 1992), controllers talk more to themselves and use oblique refer-
ences like curses or song phrases, but are nevertheless able to convey information
to others in the control room.
Gestures and other visual actions can also be used to carry out intentional
communication. These differ from consequential communication in that they are
intended, and are often used alongside verbal productions. Short, Williams, and
Christie (1976) note two forms of visual communication used to convey task infor-
mation. First is illustration, where speech is illustrated, acted out, or emphasized.
For example, people often illustrate distances by showing a gap between ﬁngers or
hands. The second form is the emblem, where words are replaced by actions: for
example, a nod or shake of the head indicates ‘yes’ or ‘no’ (p. 45). These types
of gestures have also been observed in CSCW studies (e.g. Ishii and Kobayashi,
1992; Tang, 1991).
7. Framework part three: How is workspace awareness used in
A groupware designer needs to know the situations and activities where work-
space awareness will be used, to better analyze collaborative tasks and to better
determine when groupware support is called for. Workspace awareness is used
for many things in collaboration. Awareness can reduce effort, increase efﬁciency,
and reduce errors for the activities of collaboration. This section describes ﬁve
types of activity, reported in the literature and as seen in our observational studies
(Appendix 1), that are aided by workspace awareness (e.g. Tatar et al., 1991; Clark,
1996; Tang, 1991; Salvador et al., 1996). These provide a basic set of collaborative
activities that designers can look for as they analyse work situations. The ﬁve
activities are: management of coupling, simpliﬁcation of verbal communication,
coordination, anticipation, and assistance.
7.1. MANAGEMENT OF COUPLING
Several researchers have recognized that when people collaborate, they shift back
and forth between individual and shared work, and that awareness of others is
important for managing these transitions. For example, Dourish and Bellotti (1992)
observed that people involved in a shared editing task “continually moved between
concurrent, but more or less independent, work ... to very tightly focused group
consideration of single items. These movements were opportunistic and unpre-
426 CARL GUTWIN & SAUL GREENBERG
dictable, relying on awareness of the state of the rest of the group” (p. 111).
Gaver (1991) adds that “people shift from working alone to working together, even
when joined on a shared task. Building systems that support these transitions is
important, if difﬁcult” (p. 295).
Salvador et al. (1996) call the degree to which people are working together
coupling.3In general terms, coupling is the amount of work that one person can
do before they require discussion, instruction, action, information, or consultation
with another person. Some of the reasons that people may move from loose to
tight coupling are that they see an opportunity to collaborate, that they need to
come together to discuss or decide something, that they need to plan their next
activity, or that they have reached a stage of their task that requires another person’s
involvement. A sense of awareness about what another person is doing makes each
of these situations more feasible, by allowing people to recognize when tighter
coupling could be appropriate. Heath and Luff (1995) give the example of a ﬁnan-
cial dealing ofﬁce where dealers manage coupling by carefully monitoring their
... though dealers may be engaged in an individual task, they remain sensitive
to the conduct of colleagues and the possibility of collaboration ... ‘Peri-
pheral’ monitoring or participation is an essential feature of both individual
and collaborative work within these environments. (p. 156)
So, for example, it is not unusual in the dealing room for individuals to time,
with precision, an utterance which engenders collaboration, so that it coincides
with a colleague ﬁnishing writing out a ticket or swallowing a mouthful
of lunch. By monitoring the course of action in this way and by prospec-
tively identifying its upcoming boundaries, individuals can successfully initiate
collaboration so that it does not interrupt an activity in which a colleague is
engaged. (p. 152)
Although these examples deal with a wider environment than a ﬂat shared work-
space, the idea is the same – that people keep track of others’ activities when they
are working in a loosely coupled manner, for the express purpose of determining
appropriate times to initiate closer coupling. Without workspace awareness infor-
mation, people will miss opportunities to collaborate, and will often interrupt the
other person inappropriately.
7.2. SIMPLIFICATION OF COMMUNICATION
Workspace awareness lets people use the workspace and the artifacts in it
to simplify their verbal communication and make interaction more efﬁcient.
When discussion involves task artifacts, the workspace can be used as an
external representation of the task that allows efﬁcient nonverbal communication
(Hutchins, 1990; Clark, 1996). That is, the artifacts act as conversational props
(Brinck and Gomez, 1992) that let people mix verbal and visual communication.
REAL-TIME GROUPWARE 427
Workspace awareness is important because interpreting the visual signals depends
on knowledge of where in the workspace they occur, what objects they relate to,
and what the sender is doing. The nonverbal actions simplify dialogue by reducing
the length and complexity of utterances. Four kinds of these communicative
actions have been previously observed in studies of face-to-face collaboration:
deictic reference, demonstration, manifesting actions, and visual evidence.
Deictic references. Referential communication involves composing a message that
will allow another person to choose a thing from a set of objects (Krauss and
Fussell, 1990). When transcripts of a collaborative activity are reviewed, however,
many of these messages are almost unintelligible without knowledge of what was
going on in the workspace at the time. For example, consider a fragment from a
transcript of a puzzle task (Appendix 1):
A: How about this thing ... <points to diagram> ... the tail? The only thing
that can be is ...
B: <holds up a piece>No, not that.
B: <holds up another piece>This thing? It could be that thing <points to
A: Yeah, could be that thing ...
A: <holds up another piece>Could be that thing ...
The verbal communication does not convey what people are pointing at or indi-
cating when they say “this,” “that,” “here,” or “there.” The practice of pointing or
gesturing to indicate a noun used in conversation is called deictic reference, and is
ubiquitous in shared workspaces (e.g. Segal, 1995; Tatar et al., 1991; Tang, 1991).
For example, in a ﬂight simulation experiment with two pilots, Segal (1994) found
that many of the transcribed utterances could not be interpreted without reference
to a videotape of the cockpit displays. Deictic reference is a crucial part of the way
we communicate in a shared space. As Seely Brown and colleagues (1989) state:
Perhaps the best way to discover the importance and efﬁciency of indexical
terms and their embedding context is to imagine discourse without them.
Authors of a collaborative work will recognize the problem if they have ever
discussed the paper over the phone. “What you say here” is not a very useful
remark. Here in this setting needs an elaborate description (such as “page
3, second full paragraph, ﬁfth sentence, beginning ...”) and can often lead
to conversations at cross purposes. The problem gets harder in conferences
calls when you becomes as ambiguous as here ... The contents of a shared
environment make a central contribution to conversation. (p. 36)
Demonstrations. In addition to gestures used to illustrate conversation (e.g. Clark,
1996), people use gestures in workspaces to demonstrate actions or the behaviour
of artifacts. As Tang (1989) states, “ideas are often enacted gesturally in order to
express them effectively to others, especially if they involve a dynamic sequence of
428 CARL GUTWIN & SAUL GREENBERG
actions” (p. 76). Common demonstrations include tracing a path in the workspace
with a ﬁnger or illustrating how an artifact operates. For example, Tang (1989)
observed a participant in a design session turning her hand over to demonstrate
how a card would ﬂip back and forth (p. 76).
Manifesting actions. Actions in the workspace can also replace verbal com-
munication entirely. When people replace an explicit verbal utterance with
an action in the shared workspace, they are performing a manifesting action
(Clark, 1996). Placing my groceries on the counter tells the clerk “I wish to
purchase these items” without me having to say so. However, manifesting actions
must be carried out carefully to prevent them being mistaken as ordinary actions:
the action must be stylized, exaggerated, or conspicuous enough that the “listener”
will not mistake it (Clark, p. 169). Therefore, I must place my groceries on the
counter in such a way that the clerk realizes I am making a purchase request and
not just resting my arms.
Visual evidence. When people converse, they require evidence that their utterances
have been understood. In verbal communication, a common form of this evidence
is back-channel feedback. In shared workspaces, however, visual actions can also
provide evidence of understanding or misunderstanding. Clark (1996) provides
an example from an everyday setting, where Ben is getting Charlotte to center a
candlestick in a display:
Ben: Okay, now, push it farther – farther – a little more – right there. Good.
Charlotte moves the candlestick after each of Ben’s utterances, providing visual
evidence that she has understood his instructions and has carried them out to the
best of her interpretation. This kind of evidence can be used whenever people carry
out joint projects involving the artifacts in a shared workspace.
The success of these four kinds of nonverbal communication depends on two
aspects of workspace awareness. First, and most obvious, the communicative
action must be perceived before it can be understood; if the action is invisible, it is
impossible to interpret. For example, if I cannot see that you are pointing, or what
you are pointing at, I cannot ground your deictic reference. Second, the receiver
needs to have an idea of the workspace context in which the visible actions occur,
since the meaning of the action may be ambiguous without certain information. For
example, if there are several green blocks in the workspace, seeing only that you are
pointing to a green block may not be enough information to correctly ground the
reference. Or, if you hand me an object in a way that appears to be a request, I may
need knowledge of your current activities before I can determine your expectations.
The important thing here is that the sender has to understand what the receiver
can see in order to construct useful non-verbal communications. This means
that workspace awareness is part of conversational common ground in a shared
workspace. Common ground is the mutual knowledge that people take advantage
REAL-TIME GROUPWARE 429
of to increase their communicative efﬁciency (Clark, 1996). The principle of
least collaborative effort suggests that people expend only the minimum effort
in composing an utterance that they believe is necessary for their message to get
across to the hearer (Clark and Brennan, 1991). If they can exploit common ground,
they can reduce the work that goes into communication. Without common ground,
people must do more work to compose exact, complete, and literal utterances.
Workspace awareness as common ground means that people can further simplify
their communication even without visual productions. They do this by assuming
that the other person’s awareness will help them correctly interpret highly under-
speciﬁed utterances. For example, if I believe that you know where I am and what
I’m working on, I can say something like “do you think that it will ﬁt?” instead of
“do you think that the smaller of the two arches will ﬁt at the top of the tower that’s
at the right side of the picture?,” a much more complicated and exact utterance.
7.3. COORDINATION OF ACTIONS
Coordinating actions in a collaborative activity means making them happen in the
right order, at the right time, and generally, making them meet the constraints of
the task. Coordination is necessary at several levels of granularity, from small hand
movements to large-scale divisions of labour. In addition, certain kinds of joint
activities require the concerted action of two people.
Coordination can be accomplished in two ways in a shared workspace: “one is
by explicit communication about how the work is to be performed ... another is
less explicit, mediated by the shared material used in the work process” (Robinson,
1991, p. 42). This second, less explicit way uses workspace awareness. Awareness
aids both ﬁne and coarse-grained coordination, since it informs participants about
the temporal and spatial boundaries of others’ actions, and since it helps them ﬁt
the next action into the stream. Workspace awareness is particularly evident in
continuous action where people are working with the same objects. For example,
CSCW researchers have noted that concurrency locks are less important or even
unnecessary when participants have adequate information about what objects
others are currently using; when the awareness information is available, people
can use social protocols to coordinate access to objects (Greenberg and Marwood,
1994). Another example is the way that people manage to avoid bumping into each
others’ hands in a conﬁned space. Tang (1989) saw this kind of coordination in
the physical closeness among the participants ... allows a peripheral awareness
of the other participants and their actions, as evidenced in the many ‘coordi-
nated dances’ observed among the hands of the collaborators in the workspace.
There were many episodes of intricate coordinated hand motions, such as
getting out of the way of an approaching hand or avoiding collisions with other
hands. These coordinated actions indicate a keen peripheral awareness of the
other participants ... (p. 95)
430 CARL GUTWIN & SAUL GREENBERG
Workspace awareness is also useful in the coordination and division of labour
and in the planning and replanning of the activity. As the task progresses, groups
regularly reorganize what each person will do next. These decisions depend in
part on elements of workspace awareness – what the other participants have done,
what they are still going to do, and what is left to do in the task. Based on another
person’s activities, I may decide to begin a complementary task, to assist them with
their job, or to move to a different area of the workspace to avoid a conﬂict. It may
be more efﬁcient to have the members of the group do work that is near in proximity
or in nature to what they are currently doing or have done in the past. Knowing
activities and locations, therefore, can help in determining who should do what
task next. For example, in one of the puzzle tasks we observed, the structure was
symmetric, and people would regularly choose to do the symmetrical complement
to their partner’s action immediately after the partner had completed it.
Another common behaviour in collaboration is anticipation, where people take
action based on their expectations or predictions of what others will do in the
future (Tang, 1989; Hall, 1959). People anticipate others in several ways. They
can prepare for their next action in a concerted activity, they can avoid conﬂicts, or
they can provide materials, resources, or tools before they are needed.
Anticipation is based on prediction, and people can predict workspace actions
at both small and large time scales. First, people can predict some types of events
by extrapolating forward from the immediate past. For example, if I see someone
reaching towards a pair of scissors, I might predict that they are going to grab them.
This prediction allows me to anticipate the event: I might pick up the scissors and
pass them to the reacher, I might replan my own movements to avoid a collision, or
I might reach for them myself to grab them before the other person gets them.
This kind of anticipation is integral to the ﬁne-grained coordination discussed
above. Although ordinary, anticipation is difﬁcult without workspace awareness –
in the scissors example, without up-to-the-moment knowledge of where the other
person’s hand is moving, and of their location in relation to the scissors. In addition
to this information, my prediction could have also taken into account other work-
space awareness knowledge, such as their current activities and whether they were
doing something that required scissors.
When prediction happens at a larger time scale, people learn which elements
of situations and tasks are repeated and invariant. People are experts at recog-
nizing patterns in events, and quickly begin to predict what will come next in
situations that they have been in before. Workspace awareness is again important,
but this time provides people with the information they need to determine whether
others’ behaviour match the patterns that they have learned. For example, in air
trafﬁc control, regional controllers hand ﬂights off to the Calgary controllers when
they come within 35 miles of the city. The transfer is done entirely through the
REAL-TIME GROUPWARE 431
shared workspace. The regional controller tags the aircraft’s icon, and the Calgary
controller must acknowledge the handoff by pressing a command key while their
trackball cursor is overtop the aircraft. This handoff procedure is done for each
ﬂight, so the controllers are extremely familiar with it. Accordingly, the Calgary
controllers anticipate the handoff, based on the information available in the work-
space and their experience of what the regional controllers do in this situation.
When a Calgary controller sees an incoming aircraft appear on the edge of the
radar screen, they will often move their cursor over the aircraft, waiting for the
handoff indicator from the regional controller to appear.
Assisting others with their local tasks is an integral part of collaboration, and one
that also beneﬁts from workspace awareness. Assistance was extremely common in
the tasks we observed, but not usually explicit. Often, one participant would make
some indirect statement indicating that they wanted assistance, and their partner
would look over and leave their tasks for a few moments to help out, and then
return to what they were doing. For example, one participant was unable to ﬁnd a
piece that she needed for the cathedral puzzle task (Appendix 1), and so indirectly
asked her partner for assistance:
A: Do you have another one of these guys here? <holds up piece>
B: They’re, uh, red?
B: Yep, there’s one ... <hands piece to A>
People were also able to provide assistance without a prior request. In the same
task, one participant simply reached over and placed a piece for the other:
A: Oh, and I found another triangle thing for you ... here. <places piece>
Awareness in these situations is useful because it helps people determine what
assistance is required and what is appropriate. In order to assist someone with their
tasks, you need to know what they are doing, what their goals are, what stage they
are at in their tasks, and the state of their work area. In the second example above,
the helper knew what their partner had already completed; in particular, that she
had not yet found all of the needed “triangle things,” and that adding one to the
cathedral would be beneﬁcial.
This section has outlined ﬁve kinds of collaborative activity that are aided
by greater workspace awareness; these are summarized in Table III. Groupware
designers can use this part of the framework in two ways: ﬁrst, as an analysis tool to
help them determine the degree of awareness support that is needed for a particular
work situation (since different collaborative situations involve these activities in
different amounts); and second, as a guide to determining where in the interface
that awareness support should be provided. In the next section, we discuss some of
the ways in which awareness support can be provided in the interface.
432 CARL GUTWIN & SAUL GREENBERG
Table III. Summary of the activities in which workspace awareness is used
Activity Beneﬁt of workspace awareness
Management of coupling Assists people in noticing and managing transitions
between individual and shared work.
Simpliﬁcation of communication Allows people to the use of the workspace and artifacts
as conversational props, including mechanisms of deixis,
demonstrations, and visual evidence.
Coordination of action Assists people in planning and executing low-level work-
space actions to mesh seamlessly with others.
Anticipation Allows people to predict others’ actions and activity at
several time scales.
Assistance Assists people in understanding the context where help is
to be provided.
8. Supporting examples: Applying the workspace awareness framework to
The framework describes what the elements of workspace awareness are, what
mechanisms are used to maintain it, and when it is useful in collaborative work
situations. In this section, we look at ways designers can apply the knowledge of
the framework to the design of groupware interfaces, and review a set of techniques
that can be used to provide different elements of workspace awareness information.
We give examples of how a designer can use the framework: to think about the
representation and placement of awareness information within the interface; to
analyze and categorize existing awareness techniques, displays and widgets; and
to inform the design evolution of a particular awareness widget.
We caution that these are representative and illustrative examples, rather than
as an exhaustive list of previous work. We do not attempt to explain the details
of approaches or interface widgets. Also, the awareness displays and widgets used
in these examples are oriented towards only one part of the process of maintain-
ing awareness – making information available – so designers must also consider
whether people interpret the information correctly, and whether their resulting
actions are appropriate. Our examples are also biased towards our own experi-
ences: many of the techniques presented arise from our work with the GroupKit
groupware toolkit (Roseman and Greenberg, 1996).
8.1. ORGANIZING DISPLAY SPACE
Our ﬁrst example suggests how a designer can think about the general representa-
tion and placement of how awareness information is presented within the interface.
A designer faces basic questions of where and how to display workspace awareness
REAL-TIME GROUPWARE 433
Table IV. Presentation and placement of awareness display
information in a groupware interface. We have determined two basic dimensions
that provide boundaries for some of these questions. First, when considering where
information will be displayed, the dimension of placement draws a basic distinction
between information that is situated within the workspace and information that
is presented separate from it. Situated placement implies that the information is
displayed at the workspace location where it originated, and separate placement
means displaying the information outside the workspace in a separate part of the
interface. Second, the issue of how information will be displayed suggests the
dimension of presentation: a display can be either be literal or symbolic. Literal
presentation implies that the information is shown in the same form that it is
gathered, and includes low-level movement and feedback. Symbolic presentations
extract particular information from the original data stream and display it explicitly.
These two dimensions combine to form the matrix shown in Table IV.
Of these divisions, the approach that holds perhaps the most promise for natural
and effective awareness support is the situated-literal approach. Here, awareness
information is integrated into the workspace’s existing representation, and is shown
in the same form that it was produced by another person. This approach is the
closest approximation of how awareness information appears in the real world, and
it is the only one that allows people to use their existing skills with the mechan-
isms of feedthrough, consequential communication, and gestural communication.
In addition, situated and literal information best supports the three activities in
the perception-action cycle that people use to maintain awareness: it is available
in the environment but need not be attended to all the time; it provides low-level
information that can be interpreted in light of other existing knowledge; and it
allows further exploration or action to be taken in the same context in which
the information was gathered. Situating awareness information, however, raises
the possibility that people may not notice important events; furthermore, there is
no guarantee with any awareness technique that people are going to interpret the
information correctly or use it effectively.
Two critical design elements of the situated-literal approach are embodiment
and expressive artifacts. Embodiments are visible representation of each person’s
body in the workspace – representations that have been used include telepointers
(Hayne, Pendergast and Greenberg, 1993), view rectangles (Beaudoin-Lafon and
Karsenty, 1992), avatars (Benford et al., 1995), and video images (Tang and
Minneman, 1991; Ishii and Kobayashi, 1992). Depending upon its expressiveness,
a workspace embodiment can provide information about who is in the work-
434 CARL GUTWIN & SAUL GREENBERG
space, where they are, and what they are doing, and can afford both consequential
and gestural communication. The third mechanism, feedthrough, is provided by
expressive artifacts – artifacts that maximize the amount of usable awareness infor-
mation produced for the group. Although the design of speciﬁc artifacts cannot be
predetermined, there are general strategies for designing and displaying common
types of manipulations that increase expressiveness, such as action indicators or
action animations (Gutwin and Greenberg, 1998).
One particular drawback to the situated-literal approach is that of visibility
– when information is situated in the workspace, others have to be looking at
the appropriate part of the workspace in order to see the information. This can
be a severe problem in relaxed-WYSIWIS systems that allow people to scroll to
entirely different parts of the workspace. A solution to this problem is to provide
multiple views that offer visibility to awareness information in unseen parts of the
workspace; for example, radar views (Smith et al., 1998) show information in the
entire workspace. In the next section, we map techniques from both the situated-
literal approach and other parts of the design space to the elements of workspace
8.2. TECHNIQUES,DISPLAYS,AND WIDGETS
Our second example shows how a designer can use the workspace awareness
framework to analyze and categorize existing techniques, displays and widgets.
Tables V, VI, and VII below use the elements of workspace awareness to organize
a variety of awareness displays and techniques that have appeared in previous liter-
ature. We concentrate here on real-time aspects of workspace awareness – elements
that answer the who,what,andwhere questions. The techniques are grouped
according to what workspace awareness elements are supported; some displays
appear several times since they support more than one element of awareness. This
review is intended as an illustrative and representative list rather than an exhaustive
one, and due to our familiarity with GroupKit, is slightly skewed towards solutions
that have been built with that toolkit.
8.3. CASE STUDY –EVOLUTION OF A RADAR VIEW
As an example of how the knowledge in the framework can be used, we review
the design evolution of a radar view built for the GroupKit toolkit. Radar views are
secondary windows used with a detailed view of the shared workspace; they show
miniatures of the artifacts in a shared workspace, and can also be used to show
awareness information about the participants in the session. Our original radar view
showed only the movement of workspace objects (Figure 4a). As we worked with
the display in a newspaper-layout domain, it became apparent that several aspects
of awareness were not well supported.
REAL-TIME GROUPWARE 435
Figure 4. Three versions of the GroupKit radar view. Version 4a shows object movement only;
4b adds location information by showing each person’s main view as a shaded rectangle; 4c
adds photographs for participant identiﬁcation.
Table V. Workspace awareness techniques for “who” questions
WA element (Who) Example interface techniques
(Is anyone there?)
•Participant list (e.g. Sohlenkamp and Chwelos, 1994). The most
basic awareness display, the participant list shows who is currently
logged in to the system (although several other types of awareness
information can be added to this basic idea). Presence is shown by
presence in the list.
•Embodiment solutions (telepointers, view rectangles, avatars,
video images). Since an embodiment is a representation of an
actual person, presence is shown by the existence of the embodi-
ment. In some cases, presence can also be heard if embodiments
emit sound as they interact with the workspace (Gaver, 1991).
(Who is that?)
•Participant list identiﬁes participants with a name or picture.
•Embodiments show identity through visual characteristics of the
representation, such as colour (telepointers or view rectangles),
shape and appearance (avatars), or actual images (video tech-
(Who is doing that?)
•Creation colouring (e.g. Mitchell, 1996). When activities involve
the creation of new artifacts, the objects (such as characters in a
text window) can be coloured to indicate authorship.
•Embodiment proximity. The proximity of a person’s representa-
tion to an action is a strong authorship clue in direct-manipulation
•Authorship lines (e.g. Sohlenkamp and Chwelos, 1994). Lines
drawn from actions or artifacts to a participant list to indicate
436 CARL GUTWIN & SAUL GREENBERG
Table VI. Awareness techniques for “what” questions
WA element (What) Example interface techniques
(Is anything happening?
What is she doing?)
•Activity and change indicators (e.g. Ackerman and Starr,
1995). “Change meters” placed in the interface to indicate
the occurrence or rate of activity or edits in the workspace.
•Consequential communication through embodiment.
People’s workspace representations convey both that
actions are happening, and also what actions are occurring
through characteristic motions.
•Mode indicators. Representations of the mode in which
each person is working. Modes can be shown separately
(in a participant list) or can be situated. For example,
telepointers can show each person’s mode in a drawing
program (e.g. Greenberg and Bohnet, 1991).
•Action indicators and animations. Actions that are hard to
see can be made artiﬁcially more perceptible with visible
indicators; actions that are instantaneous can be lengthened
with animations (e.g. Gutwin and Greenberg, 1998).
•Visibility of actions (Smith et al., 1998; Gutwin, Green-
berg and Roseman, 1995). Separate views of the workspace
provide visibility to actions that are in other parts of the
workspace. Radar views show the entire workspace. Over-
the-shoulder views show a miniature version of another
person’s main view. Cursor’s-eye views show the area
immediately around another person’s cursor in full detail.
•Audible actions. Others’ actions can be represented with
sound to show both existence and type of activity (e.g.
(What is she going to do?)
•Embodiment frame rate. Showing embodiments at a real-
time frame rate allows observers to accurately predict
movements and anticipate actions (e.g. Gutwin, 2000).
•Marking artifacts. Explicit notiﬁcation of future inten-
tions by visibly marking workspace artifacts (e.g. Gutwin,
Roseman and Greenberg, 1996).
(What object is she using?)
•Embodiment proximity. The proximity of embodiment to
an artifact is a strong clue in direct-manipulation environ-
•Artifact indicators. Artifacts that are currently being edited
can be represented on a separate display such as a partici-
•Characteristic sounds. Different objects can produce
different types of sounds, giving some indication of which
artifact is in use (e.g. Gaver, 1991).
REAL-TIME GROUPWARE 437
Table VII. Workspace awareness techniques for “where” questions
WA element (Where) Example interface techniques
(Where is she working?)
•Embodiment techniques show location by the position of
the person’s representation. Outside the main workspace
view, visibility techniques such as radar views are required.
•Radar or gestalt views (Smith et al., 1998; Baecker et al.,
1993). These show location using view rectangles and tele-
pointers on a miniature of a two-dimensional workspace.
•Multi-user scrollbars (Baecker et al., 1993). These show
location using view bars in one-dimensional workspaces.
•Distortion-oriented workspace representations. The visi-
bility problem can also be addressed by always showing the
entire workspace in the main view, and then using magni-
ﬁcation techniques to show detail (e.g. Greenberg, Gutwin
and Cockburn, 1995).
•Sound distance. Activity sounds can indicate distance and
location of activity by changes in volume and direction (e.g.
•Location indicators. In structured environments (such as
rooms-based systems), indications of location can be
placed on a separate display such as a participant list (e.g.
Roseman and Greenberg, 1996).
(Where is she looking?)
•Eye-contact video. Certain types of video embodiments
show gaze direction accurately (Ishii and Kobayashi, 1992).
•Embodiment position. The position of the control part of an
embodiment (e.g. the telepointer or the hand of an avatar)
is often a reasonable clue as to a person’s gaze direction.
(What can she see?)
•View rectangles. Explicit representations of another
person’s view show what they can see in detail (e.g.
Beaudoin-Lafon and Karsenty, 1995).
•Duplicate views. The over-the-shoulder view provides a
miniature of another person’s detail view (Gutwin, Green-
berg and Roseman, 1995).
•View slaving. Being able to temporarily switch to another
person’s view shows what they can see in full detail
(Gutwin, Roseman and Greenberg, 1996).
(What can she manipulate)
•View rectangles. Representations of a person’s detail view
indicate what a person can reach for detailed work; over-
views show what can be reached for large-scale manipula-
tion (often the entire workspace)
438 CARL GUTWIN & SAUL GREENBERG
Table VIII. Awareness elements supported by features of the radar view
Feature added Awareness elements Mechanism
Object movement Action, artifact Feedthrough
View rectangles Identity, location, view, reach Consequential communication
Radar telepointers Identity, location, action, intention Consequential communication
Participant photos Identity Embodiment
In analysing the drawbacks of the device for the tasks being carried out, the
WA framework was used as an analysis tool to help identify which elements
of awareness should be better supported. We determined that more information
about location, activity, and identity was required for some tasks. This led to two
redesigns. To the version in Figure 4b, we added location information with shaded
viewport rectangles and miniature telepointers, and to the version in Figure 4c, we
added portraits for participant identiﬁcation.
We also used the idea perception-action cycle to change the way that the radar
works. The ﬁrst two versions of the radar are display only, and we found that people
were having difﬁculty acting on information that they gathered from the window
(Gutwin, Roseman and Greenberg, 1996). Therefore, the third version of the radar
was made into a fully interactive secondary workspace rather than a view-only
display: people can interact with its objects, and moving the telepointer over it
lets people gesture anywhere within it. Our evaluations conﬁrm that users do ﬁnd
the later devices more useful for some kinds of collaborative tasks (e.g. Gutwin,
Roseman, and Greenberg, 1996; Gutwin and Greenberg, 1998).
The features added to the radar view, and the elements of workspace awareness
that they support, are shown in Table VIII.
9. Summary of the workspace awareness framework
Workspace awareness is the up-to-the-moment understanding of another person’s
interaction with the shared workspace. The conceptual framework sets out basic
issues that designers need to consider when building workspace awareness support
into groupware systems. The framework describes three aspects of workspace
awareness: its component elements, the mechanisms used to maintain it, and
its uses in collaboration. These parts correspond to three tasks that the group-
ware designer must undertake in supporting workspace awareness: understand
what information to provide, determine how the knowledge will be gathered,
and determine when and where the knowledge will be used. The framework is
illustrated in Figure 5, overlaid on Neisser’s original perception-action cycle. In
addition, we add a new link to the cycle (action) to indicate that people take action
based on their knowledge as well as exploring the environment.
REAL-TIME GROUPWARE 439
Figure 5. The workspace awareness framework.
The elements of workspace awareness answer who, where, when, how, and what
questions. They deal with issues like who is present and who is responsible for
actions, where people are working and where they can see, and what actions they
are performing and what their intentions are. Other elements of workspace aware-
ness consider awareness of history and past events. The elements are a starting
point for thinking about the awareness requirements of particular task situations,
and provide a vocabulary for describing and comparing awareness support in
Workspace awareness is maintained through a perception-action cycle in which
people gather perceptual information from the environment, integrate it with what
they already know, and use it to look for more information in the workspace.
Information is gathered primarily through three mechanisms. First, the presence
and movement of hands and bodies in the workspace provide consequential
communication. Second, movement and changes to artifacts in the workspace
provides feedthrough information. Third, information is gathered through inten-
tional communication, which can be either verbal or gestural. People are already
familiar with these three ways of gathering workspace awareness information, from
their experiences in face-to-face workspaces. In groupware, designers can simplify
information-gathering by using these mechanisms in their awareness displays, even
440 CARL GUTWIN & SAUL GREENBERG
though the displays themselves will likely bear little resemblance to face-to-face
Workspace awareness is useful for making collaborative interaction more efﬁ-
cient, less effortful, and less error-prone. There are several activities of collabora-
tion where the beneﬁts of workspace awareness are evident: in helping people
to recognize opportunities for closer coupling, in reducing the effort needed for
verbal communication, in simplifying coordination, in allowing people to act in
anticipation of others, and in providing context for appropriate help and assistance.
Designers can use this part of the framework as an analysis tool to help them
determine the awareness support that is needed for a particular work situation, and
as a guide to determining where in the interface that awareness support should be
The role of the framework in the groupware design process is not as a
prescriptive design guide, but rather as a structured collection of knowledge that
can assist the iterative development of awareness support. The framework iden-
tiﬁes three steps that designers should undertake – think about what information
to provide, what perceptual mechanisms to use to convey the information, and
when and where in the interface to provide the information – and provides a set
of alternatives and possibilities for each step.
The knowledge in the conceptual framework will allow designers to build more
usable groupware, and this knowledge has not previously been available to group-
ware designers in one place. However, workspace awareness is only one type
of group awareness, and the knowledge in our framework must be used along
with other tools. For example, another model of awareness in collaborative virtual
environments is the focus/nimbus model (e.g. Benford et al., 1995; Rodden, 1996).
The model offers a way to determine what the level of awareness should be for two
actors in a shared space. The actors’ physical location and the distance between
them are two important factors in the model, and states an inverse relationship
between distance and awareness – the farther you are from someone, the less aware
you should be of them. In addition, the model incorporates the possibility that
actors can affect their own degree of awareness: these capabilities are represented
in the concepts of focus and nimbus. The focus/nimbus model is concerned with
large spaces that can contain many people, and hence the focus on determining
how much awareness information should be provided. Our framework, in contrast,
is oriented towards small groups in medium-sized workspaces where it is more
likely that participants are always interested in maintaining awareness of all the
members of the group. Therefore, we see the focus/nimbus model as a higher-level
complement to our framework. The two models can work together in environments
where people can work together at both a large and a small scale – the focus/nimbus
model would operate in the large, and the workspace awareness model in the small.
REAL-TIME GROUPWARE 441
In this paper we have presented a descriptive theory of awareness for small groups
in shared-workspace groupware. Our motivation for the research is that although
the idea of group awareness shows great promise for improving groupware usabil-
ity, groupware designers do not have access to principled information about how
to support it in their interfaces. Our goal, therefore, was to provide developers with
useful knowledge about how to design for awareness in multi-user systems, and
in particular, how to design for one kind of awareness called workspace aware-
ness. The main structure of the descriptive theory is a framework of workspace
awareness that organizes the concept and that informs designers as they analyse
work situations and consider the design of awareness support. The framework is
based on sound psychological principles of what awareness is and how people
maintain it in dynamic environments. The framework can both educate designers
about the importance of awareness in groupware and help to improve the quality
of the systems that are built.
We believe that the foundations and basic structure of the framework can be
used to characterize and describe other types of awareness that affect distributed
group work. First, the perception-action cycle is a general model that can be used
to explain how people keep track of a wide variety of information in a collaborative
situation. Second, the three design issues of what information to present, how to
present it, and where and when to present it apply equally well to supporting (for
example) informal awareness and conversational awareness in groupware. Since
workspace awareness is not independent of these other types, a more compre-
hensive theory that integrates several different aspects of group awareness is
needed. Extending the framework is one of our current ongoing projects. Other
current work includes assessing the effects of awareness support on groupware
usability (Gutwin and Greenberg, 1998a) and developing new awareness displays
and devices (Gutwin and Greenberg, 1998b).
This research was supported in part by the Natural Sciences and Engineering
Research Council of Canada, by Intel Corporation, and by Microsoft Research.
Our thanks to the anonymous referees for their valuable comments and recom-
1. However, these qualities could easily be part of collaborative work: for example, in a fast-paced
multiplayer video game.
2. Appendix A brieﬂy describes our own observational studies used in the conceptual framework.
3. This is different from Dewan and Choudhary’s (1991) earlier notion of coupling, which involves
coupling between interface elements in shared interfaces.
442 CARL GUTWIN & SAUL GREENBERG
Appendix A: Observational studies used in the framework
We observed several groups performing simple tasks in physical shared workspaces, in
order to gather basic information about the uses and mechanisms of workspace awareness,
and to gain ﬁrst-hand experience with phenomena described in research literature. Findings
from these studies contribute to the structure and content of the conceptual framework. The
studies were informal and varied widely in task, group structure, setting, and realism; in
some cases, we even participated as part of the group. We did not consistently employ one
particular methodology, but in all cases we observed the collaboration and recorded our
observations. In some sessions, the collaboration was videotaped for later review.
Below, we introduce each session to give an idea of the settings and the tasks that
were observed. The ﬁrst ﬁve tasks were completed in a laboratory setting, and the ﬁnal
two were visits to real work environments. In the laboratory tasks, people were allowed
to organize their collaboration however they saw ﬁt. All of the laboratory tasks were
made-up activities, while the two real work visits involved people’s normal work activities.
Blocks and puzzles. We began our observations by asking people to complete simple
tabletop tasks with one of us as a partner. Three people each completed three different
tasks. The ﬁrst task was a jigsaw puzzle, the second was a puzzle with pentominoes pieces,
and in the third, we built a house out of toy blocks. All three tasks were carried out at an
ordinary table. These tasks took approximately 10 minutes each to complete.
String. Three dyads were asked to measure the distance between several pairs of points
on a whiteboard, using a long piece of string as a measuring tool. The points were far
enough apart that each person had to hold one end of the string. The participants did the
task in two settings: ﬁrst, in front of a normal whiteboard, and second, with a divider that
prevented them from seeing one another’s work areas. The tasks took about 20 minutes in
Cathedral. Two pairs completed a more complicated construction task, that of building a
two-dimensional plan of a cathedral using a variety of cardboard pieces. The task included
constraints (such as keeping the colours symmetrical) to encourage more interaction
between the two participants. The task took place on a large table, and participants were
allowed to move where they wished around the workspace. The cathedral task took about
40 minutes to complete.
Concept map. Three pairs were asked to complete a half-ﬁnished concept map using
a written paragraph as their guide to the entities and relationships in the map. Again,
the materials were paper and pencils, and the workspace was a large table. Pairs had to
organize a set of existing objects and relations, and then add to the diagram until the
paragraph was fully represented by the map. The concept map tasks took people about 50
minutes to ﬁnish.
Newspaper layout. Nine pairs completed a newspaper layout task. Groups were asked to
put together a two-page spread of a ﬁctional newspaper, using paper articles, pictures, and
headlines supplied to them. Groups were allowed to lay out the pages as they wished, as
long as the paper had a roughly consistent style. These tasks required about 40 minutes.
REAL-TIME GROUPWARE 443
Results of this study were reported in (Gutwin, Roseman, and Greenberg 1996).
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that ranged from story composition to page layout. In the part of the ofﬁce we observed,
ﬁve writers and two editors worked on the paper.
Air trafﬁc control. The second real work situation that we visited was the air trafﬁc control
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