To establish criteria for laparotomy, the records of 224 patients admitted with an acute pelvic fracture were reviewed. Forty-four patients underwent laparotomy; 2 had no intraabdominal injury. The mechanisms of injury was blunt trauma in 31 patients and gunshot wound in 13. All four patients who died had blunt trauma. Major or minor pelvic fracture classification did not predict intraabdominal visceral injury, except for bilateral pubic rami fractures, which were commonly associated with bladder rupture. The accuracy of the indications for laparotomy was calcualted and criteria were established. Signs of an acute abdominal disorder, the presence of a penetrating wound, abnormal findings on pyleography or cystography, persistent shock, evisceration, and diminished distal pulses, singly or in combination, had a 90 percent accuracy in indicating correctable traabdominal injury. Peritoneal lavage was less reliable, with a 57 percent accuracy. Additional criteria to be considered are enlarging palpable abdominal hematoma, fracture or dislocation with bony fragments protruding into the pelvis, signs of persistent bleeding, and rectal injury or a large perineal wound.