Subclavian artery stenosis is found in up to 25% of patients with supraaortic lesions. Bypass grafting is the recommended procedure of choice but there is still debate concerning the optimal technique. We therefore performed a retrospective analysis to determine the prognostic factors based on long-term results. Between 1974 and 1992, fifty-five patients were treated for subclavian artery stenosis. The methods used were carotid-subclavian artery bypass (KSBP, n = 40) and aorto-subclavian artery bypass (ASBP, n = 15). Indications for surgery included vertebrobasilar insufficiency (20.0%), upper extremity ischemia (20%) and the combination of both (58.2%). Arteriosclerosis was the predominant cause of disease (85.5%). Peri-operative mortality was limited to one patient in the KSBP-group (2.5%). Post-operative morbidity was significantly lower in the KSBP-group (10.0%) as compared to the ASBP-group (40.0%, p = 0.018). Relief of symptoms was achieved in 97.4% of KSBP procedures and in 92.9% of ASBP procedures. Patients were followed up for a mean period of 73.7 +/- 58.0 months. Cumulative 5-year patency rates of 71.4% (ASBP) and 83.3% (KSBP) were not significantly different between both groups (p = 0.089). Pharmacologic therapy with acetylsalicylic acid (ASA) led to a statistically significantly better 5-year patency rate (100%) as compared to the combination of ASA and dipyridamole (71.4%, p = 0.016) or phenprocoumone alone (50.0%, p < 0.001) or no anticoagulation (71.4%, p = 0.005). In our experience carotid-subclavian bypass has an excellent long-term patency rate with a low peri-operative morbidity as compared to transthoracic bypass procedures (ASBP). Therefore KSBP should be the procedure of choice to correct proximal subclavian artery stenosis. Platelet inhibitors will increase bypass patency rate significantly.