Simultaneous coronary artery bypass and carotid endarterectomy were performed in 331 patients (mean age 61 years) at the Cleveland Clinic from 1973 through 1981. Of these, 195 (59%) had Functional Class III-IV angina pectoris, 308 (93%) had multiple-vessel coronary artery disease (CAD), 68 (21%) had over 50% stenosis of the left main coronary artery, and 185 (56%) had either segmental or diffuse impairment of left ventricular function. Asymptomatic carotid stenosis was documented in 173 patients (52%), and the remaining 158 had experienced either previous transient cerebral ischemia (38%) or completed strokes (10%). Single aorta-coronary grafts were placed in 59 patients (18%), double grafts in 131 (40%), and three or more grafts in 141 (42%). Nineteen patients (5.7%) died postoperatively in the hospital. Neurologic deficits occurred in 30 patients (9.0%) and produced permanent functional impairment in 15 (4.5%). Late results have been obtained for 312 operative survivors at a mean postoperative interval of 38 months. Thirty-eight patients (12%) have died, but the 5 year life-table survival rate of the study group was identical to that of the normal population aged 61 years. Significant differences in cumulative 5 year survival rates were identified among diabetic patients (p less than 0.025) and among those receiving single rather than double (p less than .005) or multiple (p less than .01) coronary grafts. Although 18 patients (5.8%) have had late strokes, only five (1.6%) of these strokes have involved the cerebral hemisphere on the same side as combined carotid endarterectomy.