The Incident Command System (ICS) is a standardized approach to the command, control, and coordination of emergency response providing a common hierarchy within which responders from multiple agencies can be effective. ICS was initially developed to address problems of inter-agency responses to wildfires in California and Arizona but is now a component of the National Incident Management System (NIMS) in the US, where it has evolved into use in all-hazards situations, ranging from active shootings to hazmat scenes. In addition, ICS has acted as a pattern for similar approaches internationally.
ICS consists of a standard management hierarchy and procedures for managing temporary incident(s) of any size. ICS procedures should be pre-established and sanctioned by participating authorities, and personnel should be well-trained prior to an incident. ICS includes procedures to select and form temporary management hierarchies to control funds, personnel, facilities, equipment, and communications. Personnel are assigned according to established standards and procedures previously sanctioned by participating authorities. ICS is a system designed to be used or applied from the time an incident occurs until the requirement for management and operations no longer exist.