The seminal literature indicates that EMS leadership theories and practices tend to be borrowed from corporate research. Consequently, how do the corporate concepts of leadership transfer and apply to EMS critical care situations and their designated leaders? Research of this particular focus does not appear to have been completed within Emergency Medical Systems. As a result, the important question that requires research is how do the various corporate theories apply directly to the leadership role assumed by various EMS personnel? The antecedents, precursors and possible explanations of this questions will be critically examined within the research. The primary focus of the presented research is to investigate leadership constituents and structure throughout North America taken from the perspective of Emergency Medical Service (EMS) managers whose role as leaders is to provide public safety and service within their communities. The participating EMS leaders work within the domain of Ambulance and/or Fire Services in North America.