A new method for evaluating the capabilities and performance of a general hospital in masscasualty exercises is described. This method is based on the use of simulation techniques which are realistic relative to the types and availability of the manpower required and to the time consumed by the assessments, interventions, and administrative duties and demands for each casualty encountered and the total workload thrust on the hospital by the cumulative requirements of all of the casualties. The simulation can be accomplished only after the time and equipment required for every possible diagnostic, therapeutic, and administrative procedure has been assessed for the specific hospital. Thereafter, it is possible to define the exact type and quantity of resources, in terms of time and manpower, consumed cumulatively by every simulated casualty assessed and treated during the exercise. The simulated victims are selected from a pool of young physicians who are briefed thoroughly by senior staff physicians prior to the exercise. Thus, the simulated subjects are provided lists of problems and the appropriate options for treatment. They also serve as controllers in the definition of time and manpower consumed for their specific injury set. Given this setting, it is possible to assess the functional performance of a hospital as a unit and for each of its components and also realistically estimate its capacity to manage disaster victims using a simulation of a disaster situation with mass casualties.