Emotion-Centered-Design (ECD) New Approach
for Designing Interactions that Matter
Eva de Lera
Av Marqués de La Argentera 17, Barcelona, Spain
Abstract. The emotional dimension of users of information and communica‐
tions technologies (ICT) is a key aspect in user experience (UX), as designers’
main objective is to ensure users are happy (satisﬁed, engaged) with their inter‐
action designs. However, current UX design methods focus on ensuring that
eﬃcacy (success achieving a speciﬁc task) and eﬃciency (in the fastest, best way
possible) are successfully achieved. The satisfaction of the user is evaluated at
the end of the process, and evaluated in reference to the eﬃcacy and eﬃciency
of their experience. In this paper, the author presents a new approach (Emotion-
Centered-Design, or ECD) in which the key to successful interaction design
(happy users) is brought about by placing emotions at the center of the design
process, versus doing so at the end. By doing so, designers can deliver more
signiﬁcant experiences, increase user experience satisfaction, and identify new
ways to innovate in interaction design, as well as add more value to users.
Keywords:: Emotions · Usability · Design processes · Design methodologies ·
User experience · Human-computer interaction · User centered design · Aﬀective
The “happiness” (satisfaction) of a user during an ICT interaction will depend on the
eﬃcacy and eﬃciency of the interaction with the device, the context of use (location-
speciﬁc) and, in the “moment of use” (emotional/stress level at a speciﬁc point in time).
Nowadays, UX methods ensure working designs, and technology is already adapting to
the users’ context, but is ICT adapting to user’s “moments”? UX designers are designing
for people, considering a unique emotional dimension or “moment” for each person or
user, when in fact, each has many “moments”, and their satisfaction levels (evaluation
of interactions) will diﬀer depending on these. Then, how can ICT adapt to user’s many
“moments” and make users happy all the time? The objective of this paper is to introduce
Emotion-Centered Design as a way to begin considering the importance of this dimen‐
sion, and does so by proposing initial solutions and potential designs for the near future.
In other words, and as an initial example, depending on the user’s available time,
specific limitations (special needs and context included) and emotional state (level of
stress and anxiety), he or she may choose a different route to go front point A to point B.
© Springer International Publishing Switzerland 2015
A. Marcus (Ed.): DUXU 2015, Part I, LNCS 9186, pp. 406–416, 2015.
• When in a hurry, time is this person’s priority and the best route is the fastest route, a
• When this person decides to begin to ride a bicycle to work, the same person, may be
afraid of riding next to cars and choose a route with bike paths, away from danger,
this being an eﬀective solution, yet less time-eﬃcient.
• And when the person is on holidays and wanting to feel good, a scenic route may be
chosen, looking for a more engaging, stimulating and interesting experience, rather
than a simply eﬀective or eﬃcient one.
There isn’t a unique design path for one same individual, but a range of solutions, to
adjust to each of this person’s preferences, needs and overall emotional state, at a very
speciﬁc time of use of the technology (“moments of use”).
The Emotion-Centered-Design (ECD) approach places the level of stress and relax‐
ation of the user at the center of the design process of any digital interaction. This means
that, depending on this stress/relaxation level at the time of the interaction, the user’s
preferred interaction will be diﬀerent. As technology has evolved, it is now possible to
design for the user’s emotional states at any given time, and there’s no need anymore
to have users adapt to the technologies, but for the technologies to adapt to users.
To help clarify this further, we bring this example to the ﬁeld of human-computer
interaction  and use the case of online travel booking as it is one of the industries
that grew faster and it’s quite consolidated worldwide. This example shows how ECD
can bring about more satisfactory results, both to end users and the company’s running
online bookings, when applied.
According to Statistics Brain , in 2013 there were 148.3 million of travel book‐
ings made on the Internet. Out of all of these:
• 65.4 % of hotel bookings where done on the brand website (operated and managed
by the brand)
• 19.5 % of hotel bookings where done on the merchant website (e.g. Expedia/
• 11.3 % of hotel bookings took place through opaque websites where the customer
does not know the brand of the supplier (e.g. Priceline)
• 3.7 % of hotel bookings are done through retail websites where hotels pay distributors
a commission (e.g. HRS or Bookings).
The statistics clearly show consumers preference for using brand websites. There are
several hypotheses for explaining such diﬀerence; the following are just a couple of
• Brand websites usually project a lifestyle and a higher-level option to either (1) ﬁnd
out the rates or (2) make a reservation, a time-saver to user and a less frustrating
• Merchant, opaque and retail websites are similar to a marketplace, quite cluttered,
confusing, and therefore, perceived as overwhelming at ﬁrst sight, frustrating in many
occasions, and promoters on increased stress or anxiety levels.
Emotion-Centered-Design (ECD) New Approach for Designing 407
As we cannot here go deeper into the business decision variables that may aﬀect
consumer choices, the ECD approach tries to over-ride these potential hypotheses and
be proactive, by allowing consumers to choose the user experience they need at that
particular moment and context in time.
The ECD approach applied to any of the above online booking websites helps under‐
stand the user’s needs further, and deliver the best solutions for them. For example:
• An entrepreneur with family responsibilities and working long-hours needs to book
a ﬂight for a business trip and any time used in searching for this ﬂight is time that
he or she does not apply to the actual work or family. In this case, the person needs
the fastest (and cheapest) option. In ECD terms, the person’s level of stress or anxiety
is higher than usual and needs an interaction that saves him or her time.
• The same entrepreneur planning the Summer holidays with a romantic partner may
choose to do so after dinner, while comfortably sitting down in the sofa, lights
dimmed, ﬁreplace on. In ECD terms, the person’s level of stress or anxiety is low,
time is not an issue, but the contrary, the person is relaxed and needs the type of
interaction that would allows them both to savor what the next holiday would be like:
discover options, explore ideas, compare rooms, amenities, ﬁnd friends, forums, etc.
These two people (as web interactions are not only done individually) may prefer to
take the “scenic” online route (path) for planning a holiday, and they may be on the
travel website for hours that night, enjoying the experience of having multiple
In the above scenarios we see one same person using online booking with two diﬀerent
experiential needs. Current human-computer interaction and user-centered design
processes do not contemplate the importance of the emotional dimension in the design
process, and it is key to reach a fuller and more impactful user satisfaction and engage‐
ment, while also contributing to the online travel business, as more satisﬁed consumers
usually mean gaining new clients and maintaining loyalty.
2 Identifying Stress and Relaxation Levels
There are several ways for knowing the stress or relaxation level of a user. In the
Emotion-Centered-Design approach we focus on the following two methods:
• Self-reporting assessments: the person tells us how he or she feels at the end of the
interaction, or task requested by the evaluator. These measures are subjective and
therefore non-correlational or fully unreliable. The eﬃcacy of self-reported assess‐
ments has been questioned throughout the year and these may usually need to be
supported and accompanied by other measures (both qualitative and quantitative)
• Automatic measures: through aﬀective wearables , the person wears a sensor that
captures the neurological or physiological response of the user during the interaction
with the speciﬁc interface; or a facial recognition software can help co-relate facials
to emotions (most of these systems still based on Paul Ekman’s FACS) . Even
though these are objective measures, these still oﬀer many limitations, such as their
408 E. de Lera
intrusive aspect, its inability to discriminate between negative stress and positive
stress (e.g. happy) or to speciﬁcally correlate measures to exact emotions. Once again,
these measures serve as a guide to help designers in their design processes and still
will need to be accompanied and supported by other qualitative and quantitative
measures (usability, questionnaires, etc.).
Both of this stress and relaxation reporting levels are still fully unreliable, but do serve
as “red” or “green” ﬂags to designers, to aid in their design process.
Red ﬂags are used to identify what should be a speciﬁc time or place in the interaction
design, indicating further evaluation and study is needed in that particular part of the
design process. Green ﬂags indicate that a particular part of the interaction design is
both, not an obstacle and also adds value to the user.
3 Limitations of User-Centered Design
The User-centered design (UCD) process has mostly been focusing on integrating the
human characteristics and capabilities of users, and their needs at a speciﬁc point in time
. Moreover, new approaches, such as Designing for Situation Awareness, have
proposed improvements for the UCD, such as the Emotion-centered design process is
doing: “The operational concept, environmental constraints, user characteristics and
operational requirements” as the basic input of the design process . In this paper, the
Emotion-Centered Design process proposes a more dramatic change in the design
process as it’s not a mere new set of data that requires to be gathered (which it also does),
but it creates a need to place emotion at the center of the design process, to direct the
process, calling for multiple designs of a one desired person’s interaction, working
The large success and impact of UCD, applied to the newer design of new technol‐
ogies, interfaces and multiple devices, has made it possible for technology products with
interfaces to be used by a much wider audience, and also by those who did not necessarily
know much about technology, or even feared it.
One of the key processes of UCD was the creation of Personas, the creation of
ﬁctitious user proﬁles based on real yet grouped characteristics, attributes and needs of
a variety of users . These Personas have been extremely useful as a way to design
processes and have served guide the design of interfaces, as they identiﬁed the most
common needs or preferences of users, ensuring that all proﬁles incorporated the basic
characteristics of all target users. Personas help deﬁne needs, tasks and also evaluate the
interaction throughout an iterative process. Its success has been fully documented in the
literature [2, 17, 20]. Personas however are limiting in that it tries to identify the most
commonly used proﬁle (set of needs and preferences).
Moreover, the successful promotion by UCD of the need for continuous participation
of the users in the design process, through multiple iterations in the design and devel‐
opment phases brought about a major change in the Usability and HCI ﬁeld. Such iter‐
ative participation (also seen in agile development) has allowed the users to become
active participants and continuous evaluators of the product or website being designed,
ensuring a reduction of errors and frustration once the produce was launched. Its success
Emotion-Centered-Design (ECD) New Approach for Designing 409
is clearly documented in multiple case studies and scientiﬁc publications [28, 32].
However, participating participants are non-representative of a diverse society and
The current user-centered design approach and its many variants do not incorporate
the users’ global needs and preferences, as temporary and permanent, in terms of access
(include disabilities, as short as a minute as long a years), context, and emotional as well,
as their emotional state at the time of the interaction (stressed or relaxed, in terms of
time or other variables inﬂuencing the emotional state) can be a major inﬂuencer in the
satisfaction or frustration level of the user, and their sense of happiness or frustration
with the given experience.
Some of the hypothesized reasons why the emotional dimension was not incorpo‐
rated in the UCD approach and design process point to:
• Overall focus on removing frustration of navigation as opposed to focusing on gener‐
ating increased satisfaction or engagement (“satisfaction” used as a measure of
ensuring the quality of the end-design as opposed to a measure to help guide the
design, before the tasks are even set up, or the concept created).
• Lack of tools and methods to assess the “satisfaction” of users, as these are unreliable
and do not provide accurate objective measures (surveys, questionnaires and inter‐
views). Such subjective measures being unreliable based on a conﬂict of certain
variables: the context of evaluation, the actual proﬁle of people willing to participate
in an evaluation and the recurrent lack of well-wished dishonesty, possibly to please
the researchers .
• Lack of non-intrusive wearables capturing objective measures and producing reliable
It is also understandable that the changes in the technology allow for diﬀerent method‐
ologies to be set in place, as these depend on the technological solutions available, and
aﬀordable. With the current technological landscape, the growth of the online population
and the removal of the initial fear brought about by non-tech users, we are now at a new
cornerstone in which the user-centered methodologies can now integrate the emotional
dimension into the design process, and go even further, have these emotions direct the
As before human computer interaction, usability, user-experience, user-centered
design and related others focused on the eﬃcacy and eﬃciency of use, followed by a
satisfaction-of-use assessment measuring “the feedback of user’s attitude, perceptions,
and feelings about the service” , the current landscape allows for a major change in
the design process to incorporate this “satisfaction” measure at the center and beyond
the satisfaction of that interaction scenario, to help guide designers in the design process,
and creating diﬀerent interactions based on the diﬀerent satisfaction or emotional
4 The Emotion-Centered Design (ECD) Approach
The Emotion-Centered-Design approach is inspired on the “satisfaction” measure objec‐
tive used-to-date in HCI, UCD and other user experience methods, and aims at going
410 E. de Lera
beyond these past practices to deliver more impactful interaction experiences and
designs. ECD proposes to do so by placing emotions in a central phase of the design
process in which these serve to guide the design process, as opposed to evaluate it,
guaranteeing more signiﬁcant and valuable results.
Emotions are not new to user experience; it is an area of expertise that several UX
professionals have been ﬂirting with for the past years. The emotional dimension of
users has long been a focus of interaction designers [12, 22, 23] and research clearly
shows that such variable is a key to a successful interaction design. The challenge being
that there are no clear methodologies or sets of methodologies that help incorporate such
dimension in an objective, easy and eﬃcient way. The ECD approach aims to ensure
that the concerns, intuitions and knowledge in regards to the importance of this dimen‐
sion in the interface design ﬁeld ﬁnds a way to reach professionals around the world that
are craving for solutions to help, not only improve their products, but the satisfaction
level of their users in a way beyond removal of frustration, and in a more engaging and
added-value way. And to do so, emotion has to be looked at from a bigger distance, from
a global point of view for the experience, and not as only a part of a concrete designed
5 Opening-up to the Emotional Dimension
Just as designers must understand their users’ needs, characteristics and behavior, is also
necessary to understand designers themselves. Human beings tend to do what had previ‐
ously worked for them, insist in their practices and ways of doing things and many times
ﬁnd themselves resistant to change . As the need to understand and integrate the
emotion dimension has well documented and alive for decades, the user experience
community has only entered superﬁcial or peripheral stages, and not seriously enough
to make the leap that user experience needs to make, to innovate in user experience by
looking at the design process from an emotion-centered perspective, instead of a task-
centered perspective which incorporates the user at the center.
Integrating the emotional dimension requires for all of those involved in the design
process to be open to new ways of doing things, challenge current methods and incor‐
porate new ideas (often meaning people with diﬀerent talents and experiences).
5.1 The Case of Mobile Phones
A great example of the above-described situation is what has taken place in the mobile
industry during these past years, since these were able to access the Internet and the
many services oﬀered through them (e.g. email).
Most mobile manufacturing companies (often lead by engineers) have designed and
competed with similar products (Nokia, BlackBerry, Samsung, Erikson, Etc.). During
the annual Mobile World Congress, a gathering of the top mobile industry players
became a showcase of similar products trying to compete amongst themselves. During
the mobile fair, visitors are able to conﬁrm that mobile devices have been designed for
Emotion-Centered-Design (ECD) New Approach for Designing 411
similar Personas and for the tasks these had been planned to execute. The phones
displayed and showcased during the 2002 Mobile World Congress:
– Were mostly black
– Had small buttons with multiple functions each
– Used the same number keyboard to type text
– Lacked interface color and aesthetics
– Used technical language
– Hard to set up (settings)
– Displayed cluttered menus
– Displayed as luxurious items (following a display design similar to those found in
New York Fifth Avenue jewelry stores)
– Supported by visual materials representing the young and mature executive world
(suits, success, beauty, perfection, etc.)
– Geared to executive professionals
– Geared to men.
When the ﬁrst Apple’s iPhone was launched in 2007 , it was mentioned by Time
Magazine as the “Invention of the Year” . This new mobile phone had broken with
what had been done to-date and for the past 9 years has been rated the highest in user
satisfaction: “For the ninth consecutive study, Apple ranks highest among manufacturers
of smartphones in customer satisfaction. Apple achieves a score of 855 and performs
particularly well in physical design and ease of operation”. . What had apple done
diﬀerently? Apple challenged the status quo of the mobile industry and made its initial
breakthrough by making the following changes:
• Geared to a much wider population through ease-of-use characteristics.
• Integrated aesthetics into the physical design of the device and the interfaces.
• Used a simple terminology, easy to understand by a wide variety of users, mostly
• Understood the basic needs of this wider audience and provided easy-to-use functions
(e.g. photo/video camera, applications and games).
• Amongst other improvements related to performance, features, operations and
Up until that time the mobile industry had been implementing UCD methodologies in
their design processes in such a way that it actually limited their capability to really
satisfy and engage the user, and expand their market reach. The narrow focus in target,
eﬀectiveness and eﬃciency became an obstacle to growth and innovation. Evaluating
“satisfaction” of the interaction was not a guarantee of “satisfaction of the user”. In part,
most mobile brands had focused on the executive work force and the technology savvy,
party because it was unthought-of that other type of users would pay a large sum for
such a device. For years, their assumptions, possible fear to risk and lack of multi—
disciplinary teams, impeded mobile brands from identifying a major gap in the mobile
industry, the people:
• The grandparents wishing to receive current photos from their loved ones.
• The teenagers wishing to exchange photos with their peers.
412 E. de Lera
• The lovers wishing to send love texts and visuals to each other.
• The impatient wishing to entertain themselves while waiting in line, on the bus or at
the doctor’s oﬃce.
• And every person who wished something more personable was available to them (a
daily horoscope app, a driving-test app, an cloud-expense recording tool, etc.).
iPhone not only delivered a new brand of mobile phone, but a personalized experience
that would add value to their wide range of users, would bring perceived happiness. The
App Store allowed for the existence of multiple solutions, providing a vast variety of
choices ensuring that each person would ﬁnd some solution, service or product that
would adapt to his or her personal needs.
When the emotional dimension is placed at the center of the design process, and
before (such as Apple did with the iPhone), the experience becomes richer and more
engaging, not only removing user experience obstacles but also actually adding new
values to the user experience. Variables such as graphic design, use of speciﬁc colors,
layouts and other visual aspects (aside from actual physical aspects of the product) are
key in user experience and not just a layer that is used to paint over a lo-ﬁdelity prototype,
but also the layer directing the design of prototypes. By also taking into account the
user’s emotional dimension (including lifestyle preferences, psychographics and stress/
relaxation state levels), the ECD approach brings about a need to re-think the design
process and methodologies used to date, and generate new experiences, enhanced expe‐
riences, interactions and products.
5.2 The Case of Online Learning
Some early approaches to integrating the emotional dimension of users into the
design process are found in the field of online learning, and virtual environments,
as such is the case at the Universitat Oberta de Catalunya  and their research
toward the Joy of Learning [7, 8, 10]. At UOC, the researchers developed different
approaches for measuring the affective dimension of learners in an objective
manner, to account for this dimension and incorporate it in the design of the online
learning environment, including a study that incorporates a method of triangulation
of pupil-size data, emotion heuristics and self-assessment methods . The Ten
Emotion Heuristics, the Enjoy Guidelines and the Joy of Learning have been early
efforts for integrating these emotional variables into the design process of online
learning experiences. Emotion-Centered-Design represents an evolved approach
based on the previous work done in online learning [9, 10], one in which incorpo‐
rates the previous emotion research, findings and experiences, and proposes a new
methodology for ensuring that emotions take the leading role it needs to ensure that
designs go beyond satisfying users and into enriching them.
6 One Person, Multiple Paths
The Emotion-Centered-Design approach presents a new design process that changes the
diagram of a design methodology process in which the “pieces” or elements stop looking
Emotion-Centered-Design (ECD) New Approach for Designing 413
like a circle or spiral indicating the need of iteration, and the graphic begins to look like
a tree that sprouts several branches, a tree being a metaphor for a given person. ECD
proposes that design methods do not use unique paths but multiple paths for moments
of use, as opposed to proﬁles. A need to design diﬀerent experiences for diﬀerent
moments, and people will convene and coincide in their choice of experience depending
on their “moment”.
According to ISO 9241-201:2010’s deﬁnition (formerly known as ISO 13407) [14,
16], user experience includes all the users’ emotions, beliefs, preferences, perceptions,
physical and psychological responses, behaviors and accomplishments that occur
before, during and after use. The ISO also list three factors that inﬂuence user experience:
system, user and the context of use. However, this deﬁnition does not contemplate the
variability of emotions over time (and this may be within an hour), being this key to
Emotion-Centered-Design. This “emotional” variability must be taken into account
before initiating a design process, deﬁning and prioritizing goals, tasks and needs.
Assuming that people’s emotional dimension stays at one same level throughout the
person’s day, or life, is unrealistic and will lead to limiting the designer’s knowledge
and therefore, negatively inﬂuence the design, and the user experience. Understanding
the inconsistency and variability of users will help provide the measures that allow them
to either choose their preferred experience for that moment/time/context or to be auto‐
matically oﬀered (prompted) the right design, or interaction path, matching their
emotional scale at the time of use.
The Emotion-Centered-Design approach invites UX designers to continue applying
their design methods, yet to moments, levels of stress and other emotional related poten‐
tial interactions, as opposed as to the people or users (Fig. 1).
Fig. 1. Visual representation of the Emotion-Centered-Design approach, multiple paths for one
same user at any given time.
414 E. de Lera
The Emotion-Centered-Design approach here introduced presents a new method for
designing highly satisfactory user experiences, by taking into account people’s range of
“moments” throughout their days and lives, as opposed to designing interactions for a
person’s proﬁle. By doing so, this approach invites user experience professionals to
undertake a major revision in their methods, to introduce the necessary design needs,
technologies and solutions to ensure that people’s variability and diversity is taken into
Implementing ECD can be done today by oﬀering users the option to choose the way
they feel, so their choice provides them with the right interaction. In the future, this could
be done through sensors, and other existing – of future – technologies. The way to
implement such call-for-action from the user can be as creative and innovative as
designers design, from a pop-up window, to a top-left button, or through an app that
pushes that information onto all devices and eﬀects behavior, or via a new key added to
all keyboard, or. What’s important is that the users’ moments are taken into account and
that they enjoy, and are really satisﬁed, with their online experiences.
Acknowledgments. We thank the all research, professionals and colleagues, who throughout
the year supported and provided helpful comments on previous revisions of this document.
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