In a patient having common carotid artery occlusion complicated with contralateral internal carotid artery stenosis, a saphenous vein bypass graft was performed from the contralateral external carotid artery to the ipsilateral external carotid artery simultaneously with contralateral carotid endarterectomy. The bypass was patent 1 year later and the patient was free from fainting spells.Among a number of the reconstructive surgical procedures, this ''half-collar bypass'' can be placed adequately in the subcutaneous soft tissue so that head or mandibular movement does not displace or compress the graft. Intraoperative hemodynamic measurements were considered useful in determining surgical options.