Cases of motor vehicle trauma victims who died after arrival at a hospital were evaluated in both Orange County (90 cases) and in San Francisco County (92 cases), Calif. All victims in San Francisco County were brought to a single trauma center, while in Orange County they were transported to the closest receiving hospital. Approximately two thirds of the non-CNS-related deaths and one third of the CNS-related deaths in Orange County were judged by the authors as potentially preventable; only one death in San Francisco County was so judged. Trauma victims in Orange County were younger on the average, and the magnitude of their injuries was less than for victims in the San Francisco County. We suggest that survival rates for major trauma can be improved by an organized system of trauma care that includes the resources of a trauma center.