The origin in the practice of providing critical incident stress management and support services to members of law enforcement can be traced back to the military. This type of trauma experienced by military soldiers in combat is similar to the trauma endured by law enforcement officers. Therefore, the law enforcement profession adopted the best practices of the military. The application of best practices can be a highly effective way to deal with complex and crisis-oriented problems. Copying successful tactics of other agencies dealing with similar problems becomes an effective and efficient strategy. A survey was conducted in 2003 to ascertain what agencies and organizations have done to support personnel during major critical incidents. This paper includes 11 Federal, State, and local organizations based on accrued unique experience responding to the psychological demands associated with extraordinary critical incidents and mass disasters. In addition, five best practices emerged from these programs which are universal and should be considered when developing a strategy; they include: early intervention, complete care, peer support, specialized training, and tactical intervention. Five core competencies as features of a best practice model were presented and included: assessment and triage, crisis intervention with individuals, small-group crisis intervention, large-group crisis intervention, and strategic planning. The future of critical incident management should consider the expansion of early intervention services with pre-crisis expectation training and early warning screening.