The correctness of the clinical diagnoses of all victims who died of an acute lethal injury of the trunk at the Department of Orthopaedics and Traumatology, Helsinki University Central Hospital in 1975–1976 was investigated. A clinicopathologic comparison on the injuries as of the time of death and severity of the trauma complex resulted in the following main observations: About 80% of all lethal injuries, 70% of the associated severe lesions, and 80% of the other more minor injuries were correctly diagnosed by clinical means with an overall accuracy of 74.5%. When victims were dead on arrival, 50% of the injuries were diagnosed by plain physical examination. When the patient died within 24 hours, 80% of the injuries were clinically diagnosed, and when the patient died between 1 and 7 days postinjury the rate was 90%. Injuries of the heart and great intrathoracic vessels, ruptures of the liver and spleen, as well as medullary contusions remained most often undiagnosed in patients who died within a few hours. Of all clinically diagnosed injuries, of which one was severe, 5.7% were not noted at autopsy.