Resuscitation of patients with cardiac asystole or ventricular fibrillation by thoracotomy for cardiac massage combined with artificial ventilation has rarely been successful in the authors' experience. In the ten-year period from 1950 through 1959, there was only one case of successful resuscitation outside of the operating room postanesthesia area, with emergency thoracotomy for massage. In contrast, with external methods, 33 patients were successfully resuscitated and were discharged from the hospital in the four-year period from 1959 through 1963. One successful case required more than three hours of external massage and ventilation, emphasizing the value of sustained efforts in certain cases. On the basis of this experience, external massage combined with artificial ventilation appears to be the method of choice for the management of cardiac arrest or ventricular fibrillation. Direct open cardiac massage would appear to be indicated where the chest is already open or where cardiac tamponade is suspected.