This study describes the experience in a major university hospital for a year before and a year after the institution of a trauma service. Demographic data and severity of injury were similar before and after the trauma service was instituted. Nonetheless, mortality for all trauma patients admitted to an intensive care unit decreased somewhat (from 16.1 to 11.8 percent) in the second period of study. When outcome for trauma patients admitted to the surgical intensive care unit was examined, the differences was more impressive, with a reduction in mortality from 27 percent to 6.1 percent. This reduction seemed to be due largely to a decrease in the number of patients who died from sepsis, multiple organ failure, or both. We suggest that trauma care can be significantly improved by an organized approach to the care of the multiply injured patient. A powerful argument can be made for organizing care of injured patients in major hospitals along the lines of a dedicated trauma service.