The elephant trunk technique is a novel staged procedure for the treatment of an extensive thoracic aortic aneurysm. Occasionally, entrapment or obstruction in the smaller lumen occurs with the use of the elephant trunk technique in aortic dissection. The general procedure is to excise a generous portion of the dissecting septum distally for a chronic dissecting aneurysm of the descending thoracic aorta. We present the "two elephant trunks" technique. In this procedure, a single side-branched graft is placed in the descending aorta without excising the dissecting septum during a first-stage operation. This modification is simple to perform and has the possibility to prevent interval rupture for a chronic dissecting aneurysm.