In a study of 103 patients surviving carotid endarterectomy, follow-up information was obtained from all patients over a period of time extending to four years. This was done so that better decisions could be made regarding recommendations for contralateral carotid surgery. In this follow-up study, only three patients had contralateral surgery. Three additional patients had events clearly in the territory supplied by the contralateral carotid artery, and no patient suffered a contralateral stroke. There were an additional four patients who suffered stroke in territory not supplied by the contralateral carotid artery. In addition, four patients experienced classical transient ischemic episodes referrable to the operated carotid artery and ten patients experienced nonclassical cerebral ischemia. Seven of the 103 patients died at times remote from the carotid surgery of nonstroke cause.