[The principal physician in emergency medicine].

The implementation of an experienced pre-hospital care emergency physician as an on the-scene medical command officer (MCO) within the emergency medical service (EMS) is an essential prerequisite to guarantee qualified medical supervision during mass-casuality incidents (MCI). The MCO has four basic functions. Within the administration of the EMS system, he is responsible for the medical aspects of strategic planning for the MCI response. During the MCI the MCO is responsible for the overall assessment of the situation, triage, and supervision of medical treatment by physician and non-physician providers. Aside from extensive personal experience in pre-hospital care, the MCO needs special training to be qualified for this position. State EMS laws provide the legal basis for the MCO within the EMS system.