An extraperitoneal approach for aortofemoral bypass has proven superior to the transperitoneal approach. The incision starts at the tip of the eleventh rib and extends obliquely downward to 2 inches above the femoral point, where it turns further downward over the femoral artery. This approach is especially suitable for a reversed L-shaped prosthesis which extends from the aorta directly to the left femoral artery and crosses the abdomen subcutaneously to the right groin, where an anastomosis is made with the right femoral artery. The operation is simple and rapid. Morbidity is reduced and recovery is accelerated. The same incision is used to perform aortoiliac endarterectomy. Fifteen patients with occlusive disease and twenty-one with aneurysms received reversed L-shaped prosthesis through an extraperitoneal approach. The procedure was superior to that involving a transperitoneal approach to the aorta and the reversed L-shaped graft was superior to the Y graft for replacement fo the iliac arteries.