Commanding an EMS incident requires an enhanced medical branch director’s command organization. These command changes are discussed in detail during the simulations. Span of control using division and groups, are detailed. EMS simulations teach the lessons learned from NTSB and NIOSH investigations as well as prior experiences of medical branch directors. An enhanced understanding is given by demonstrating how issues have resulted in initiating progressive medical branch triage, treatment, transportation, and medical communications. These skills are based on research data from various incidents including failure to complete and obtain successful size up information (survival scan/ triage), recognizing how and what resources are needed, and understanding the dynamics of a major medical response. Medical branch director presence provides effective leadership during the initial stages and during the duration of this type of incident and will contribute drastically to the successful outcome of the EMS incident. Simulation instructors will teach how to handle civilian rescues, active shooter incidents, large-scale medical incidents and they will address current issues facing emergency medical personnel.