The records of 437 patients with blunt abdominal trauma admitted to Charity Hospital, New Orleans, from 1967-1973 have been reviewed and computer-analyzed. There was an 80% increase in the incidence of blunt abdominal trauma when compared with the preceding 15-year experience. Forty-three per cent of all the patients presented with no specific complaint or sign of injury. Blunt abdominal injury was usually diagnosed preoperatively using conventional methods including history, physical examination, and routine laboratory tests and x-rays. Abdominal paracentesis via a Potter needle had an 86% accuracy. The incidence and management of specific organ injuries with associated morbidity and mortality have been discussed. Mortality and morbidity continue to be significant in blunt abdominal trauma. Isolated abdominal injuries rarely (5%) resulted in death, even though abdominal injuries accounted for 41% of all deaths. Associated injuries, especially head injury, greatly increased the risk. The insidious nature of blunt abdominal injury is borne out by the fact that more than one-third of the "asymptomatic" patients had an abdominal organ injured. A high index of suspicion and an adequate observation period therefore are mandatory for proper care of patients subjected to blunt trauma.