During three years, from January 1975 through December 1977, the authors saw six cases of traumatic left diaphragmatic hernias, all of whom survived. All were males aged 17 to 56 years, with an average age of 30 years. Four (67 percent) of the cases resulted from blunt abdominal trauma while two (33 percent) were due to stab wounds of the left lower chest. Admitting chest x-ray findings were diagnostic for all acute hernias due to blunt trauma and for all hernias presenting with a delayed interval. Digital exploration of all penetrating lower chest wounds is recommended by some authors if exploratory laparotomy is not contemplated. Our preferred approach for the repair of the hernias includes (1) laparotomy for all acute cases, (2) thoracotomy for delayed cases, and (3) separate abdominal thoracic incisions whenever a combined approach is considered necessary. The repair should be carried out in two layers with nonabsorbable sutures.