The purpose of organized trauma systems is to ensure the expeditious transfer of seriously injured patients to the facility best equipped to care for their injuries. Patients are referred to our trauma center, either by ambulance or helicopter, directly from the scene or through interhospital transfer. We examined the difference in outcome between those patients sent directly to the trauma center versus those seen at other hospitals and subsequently referred to the trauma center. Our hypothesis was that a delay at the referring hospital is detrimental to patient outcome. Adult trauma patients with Injury Severity Scores > 15, treated over 16 months from July 1, 1994, to October 31, 1995, were studied. Patients who survived 24 hours experienced significantly shorter intensive care unit (14 vs 10 days; P < 0.05) and hospital (21 vs 16 days; P < 0.05) lengths of stay when taken directly to the trauma center. In addition, there were significantly fewer deaths in patients with a probability of survival > 0.5 and a slightly lower overall mortality in those patients who survived at least 1 day. This study demonstrates that patients with major trauma taken directly to the trauma center had shorter hospital and intensive care unit stays and lower mortality. The study supports the paradigm that, when possible, major trauma patients should be sent to trauma centers directly from the injury scene.