Disaster can strike anytime, anywhere. It takes many forms—a hurricane, an earthquake, a tornado, a flood, a fire, a hazardous spill, or an act of terrorism. An incident can build over days or weeks, or hit suddenly without warning. ICS is the national standard for response. The Incident Command System (ICS) helps ensure integration of our response efforts. ICS is a standardized, on-scene, all-hazards approach to incident management. ICS allows responders to adopt an integrated organizational structure that matches the complexities and demands of the incident while respecting agency and jurisdictional authorities. A poorly managed incident response can undermine our safety and well-being. With so much at stake, we must effectively manage our response efforts. Although most incidents are handled locally, partnerships among Local, Tribal, State, and Federal agencies as well as nongovernmental and private-sector organizations may be required. As partners, we must respond together in a seamless, coordinated fashion. The ICS SMARTbook provides a detailed explanation of ICS as outlined in FEMA Emergency Management courses 100, 200, 300, 400, 700, 703, and 800; including 2015 updates. It is designed to serve as an introduction to ICS concepts, methods, and organization, as a pocket reference for experienced responders, or as a desk reference for emergency planners, community leaders, or any responder involved in the Multiagency Coordination process. Incident Command System chapters and topics include ICS Purpose, Features and Principles; ICS Command and Staff Functions; ICS Leadership and Management; ICS Dealing with Complexity; ICS Planning; ICS Briefings and Meetings; ICS Organizational Flexibility; ICS Incident and Event Management; ICS Resource Management; ICS Resource Management Process; ICS Demobilization; ICS Terms and Definitions; and ICS Forms.