The 1973 Emergency Medical Services System Act in the United States mandates that one of the 15 functions to be performed by every EMS system is coordinated disaster planning. Implicit in the legislation is the assumption that everyday emergency medical service (EMS) systems will be the basis for the provisions of EMS in extraordinary mass emergencies, or in the language of the act, during “mass casualties, natural disasters or national emergencies.” Policy interpretations of the Act specified that the EMS system must have links to local, regional and state disaster plans and must participate in biannual disaster plan exercises. Thus, the newly established EMS systems have been faced with both planning for, as well as providing services in large-scale disasters.