During the period between November 1986 and November 1988, 13 consecutive patients with Stanford type A aortic dissection (8 acute and 5 chronic) were treated as follows: (1) urgent operation for cases with pericardial tamponade or severe heart failure, (2) initial medical treatment followed by elective operation for acute but stable cases or chronic cases, and (3) routine use of open distal anastomosis or selective cerebral perfusion. One patient died during medical treatment: 5 patients were operated on emergently. The remaining 2 acute and 5 chronic cases were operated on electively. There were no operative deaths, neurological disturbances, or late deaths. It is suggested that acute dissection of the ascending aorta requires immediate surgical intervention, especially when the entry is in the ascending aorta. On the other hand, it is also suggested that one could avoid emergency operations in selected cases with retrograde extension of the aortic dissection.