Better epidemiologic knowledge of the mechanisms of death and of the types of injuries and illnesses caused by disasters is clearly essential to determining the appropriate relief medications, supplies, equipment, and personnel needed to effectively respond to such emergencies. The overall objective of disaster epidemiology is to measure scientifically and describe the health effects of disasters and the factors contributing to these effects. The results of such investigations allow disaster epidemiologists to assess the needs of disaster-affected populations, efficiently match resources to needs, prevent further adverse health effects, evaluate relief effectiveness, and plan for future disasters.