Between 1970 and 1976, 34 cases of traumatic ruptures of the diaphragma were observed and treated at the Surgical Clinic of the University of Würzburg: 23 acute ruptures and 11 delayed diagnostic ruptures. The etiology and mechanism of the rupture are discussed. A predominency of left over right ruptures occured in 90% of cases. In only one case there was an open rupture of the right side. Among associated abdominal lesions, ruptures of the spleen are the most frequent. Among skeletal associated lesions, one observes most frequently, fractures of the ribs. In 4 acute cases, there were no herniated organs. In the 11 patients were diagnosis was delayed we always found herniated viscera. Symptoms and diagnostic means are discussed. Traumatic rupture of the diaphragm is an absolute surgical indication. In acute cases we attempt the repair through a laparotomy; delayed cases should be treated by thoracotomy. Among 23 cases operated in emergency, 3 died because of associated lesions. Operative mortality was zero in the 11 patients with delayed diagnosis.