One hundred ninety-four patients underwent 222 operations for femoral-popliteal arterial occlusive disease between 1957 and 1965. The results of operative therapy employing synthetic bypass grafts, thromboendarterectomy, and autogenous saphenous veins were assessed by determining the accumulative patency rates for the three operative methods, the incidences of subsequent major amputations, and the degree of symptomatic relief (fig. 1, tables 9 and 10). The 2-year accumulative patency rates for synthetic bypass grafts, thromboendarterectomy, and saphenous vein bypass grafts were 28%, 50%, and 63%, respectively (table 8). Subsequent major amputations were performed in 37%, 27%, and 12% of the extremities in the three groups. Improvement in symptoms occurred in 33%, 48%, and 73% of the patients in the respective groups. When grouped according to severity of presenting symptoms and signs and the status of the arterial outflow by arteriography, patency rates were highest in the vein graft group and lowest in the synthetic graft groups. The patency rates after endarterectomy in those extremities with severe symptoms and poor arterial outflow tracts were similar to those of the synthetic graft group.