The federal government plays a significant role in emergency management, which generally refers to activities associated with avoiding and responding to natural and human-caused hazards. Emergency management in the United States is highly decentralized and contextual in nature: activities often involve multiple jurisdictions as well as a vast number of agencies, nongovernmental organizations, and private sector entities. In addition, the number and type of actors involved in an incident will vary tremendously depending on the context and severity of the event. Similarly, the legal framework through which emergency management functions and activities are authorized is also decentralized and stems from multiple authorities. Congress annually appropriates funds for a wide range of activities and efforts related to emergency management. For example, between 2005 and 2011 Congress provided an average of $12 billion annually to the Federal Emergency Management Agency, the lead federal agency responsible for disaster relief through regular and supplemental appropriations. Congress has also invested over $120 billion through various federal agencies to help the Gulf Coast Region recover from the hurricanes that hit the Gulf Coast in 2005 and 2008. In recent years congressional interest in emergency management has focused on funding, program administration, and program coordination-both among federal agencies and state emergency management agencies. This report provides an introduction to the principles and foundations of federal emergency management in the United States and a description of the activities of the federal agencies that provide assistance, focusing primarily on the Federal Emergency Management Agency, but also including information on the National Guard, Department of Agriculture, Department of Defense, Army Corps of Engineers, Department of Health and Human Services, Department of Housing and Urban Development, Department of Transportation, Environmental Protection Agency, Forest Service, and Small Business Administration. This report is designed to provide Members of Congress and congressional staff with a general overview of principles and foundations of federal emergency management in the United States as well as the types of activities provided by various federal agencies. The report begins with a description of the four phases of emergency management: (1) mitigation, (2) preparedness, (3) response, and (4) recovery, and includes examples of some of the activities that take place in each of these phases. The report then discusses a recent movement at the federal level to carry out these phases of emergency management through a system of frameworks. The frameworks include (1) the National Prevention Framework, (2) the National Protection Framework, (3) the National Mitigation Framework, (4) the National Response Framework, and (5) the National Disaster Recovery Framework. The frameworks are used to designate roles and responsibilities and coordinate various activities. Next, this report describes the process for requesting federal assistance for major disasters, emergencies, and fire suppression. The declaration section also includes brief summaries of the types of assistance provided through each type of declaration. This discussion is followed by description of federal-to-state cost shares, how federal assistance is funded, and the process through which FEMA requests assistance from other federal entities. The section then provides a description of the close-out process-the process in which FEMA terminates its recovery efforts. The report includes a discussion of key federal laws and policies that influence federal emergency management, and concludes by highlighting some of the federal activities that take place in response to emergencies and disasters.