Of 174 multiple trauma patients undergoing abdominal CT examination for suspected abdominal trauma, 65 patients had 109 chest injuries detected by abdominal CT, chest film, or both examinations. Forty-one patients had 55 chest injuries at the base of the thorax which were not detected on the initial chest film. The most frequent chest injuries detected only by CT were pneumothroax, fracture (rib, thoracic spine, and sternum), lung contusion, aspiration pneumonia, hemothorax, and post-traumatic atelectasis. Seven patients whose chest injury initially was seen only at abdominal CT required treatment of the injury, suggesting that a variety of chest injuries which may vitally affect patients can be detected early in multiple trauma patients by abdominal CT, and that all abdominal trauma CT scans should be scrutinized for signs of a chest injury.