Data on 22,312 admissions to the San Diego County Trauma System were used to identify 185 trauma patients admitted repeatedly to trauma units. These patients were compared with the entire group of nonrepeating trauma patients admitted during the 80-month period of the study. In comparison with nonrepeaters, the repeaters were younger, were more often men, were more often Black, and were much more frequently victims of assault. Forty-eight percent of the repeaters were injured by the same general mechanism on both admissions.