Healthcare professionals require a unique knowledge base to function effectively during a hospital's response to a mass-casualty incident (MCI). A survey of 128 physicians, nurses, and emergency medical technicians involved in trauma care was conducted to assess their knowledge base and how it affected their decision-making in response to a MCI following a terrorist bombing. Three-quarters of the study group responded that = or >20% of the surviving victims were critically injured. Only half of the responders indicated that the main objective of medical management is identifying and treating patients with critical injuries. Forty percent of responders indicated that they would not triage a critically injured victim to immediate care. This survey indicates that further education in the principles of MCI management should be based on critical evaluation of the literature.