The purpose of this paper is to identify factors associated with improved utilization of health care resources in the treatment of patients with injury. A prospective cohort study was conducted of all trauma patients admitted to a trauma center from April 15, 1987 to February 28, 1988. Altogether, 877 patients were entered into the study: 673 (76.7%) scene patients, and 204 (23.3%) interhospital transfers. The mean length of stay (LOS) for scene patients was 12 days, with mean charges of $8,781, whereas the mean LOS of interhospital transfers was 18 days, with mean charges of $16,734. When controlled for confounding variables, the scene patients had significantly shorter LOS and charges than matched interhospital transfers. This difference was more pronounced for the air-transported patients than for ground-transported patients. The elderly utilize more resources than young patients when matched for severity of injury. It is beneficial to the patients and the health care system to have severely injured trauma patients transported directly to a trauma center from the scene of an injury. Helicopter emergency medical services can enhance the ability of a trauma care system to decrease health care costs.