This report describes successful staged surgical repair in 2 patients with dissection of the upper descending thoracic aorta (DeBakey type III) with coexisting discrete Marfan's aneurysms of the ascending aorta. Initial repair of the descending aortic dissection was done through a left thoracotomy using a transverse aorta--femoral artery shunt in 1 patient and a left ventricular apex--femoral artery shunt without systemic heparinization in the other. Emphasis is placed on the need for pharmacological reduction of blood pressure during aortic cross-clamping as well as the use of a shunt to prevent dissection of the ascending aortic aneurysm. In both patients, subsequent repair of the ascending aortic aneurysm was accomplished using composite graft replacement of the aortic valve and ascending aorta. This operation is advised for such patients even in the absence of notable aortic valve incompetence.