One hundred and twenty four percutaneous transluminal angioplasties performed over a 5 year period for lower extremity arterial occlusive disease were reviewed to evaluate clinical efficacy and define parameters of success. Technical success was achieved in 82%, clinical success in 71%. The important predictive variables were severity of disease, anatomic site and length of diseased vessel segment. Best results (94% success rate) were obtained in the proximal single segment lesion with lesser initial disease as reflected by flow study, calf vessel runoff and claudication as the indication for treatment. The poorest results (33% success rate) were obtained in distal vessels with multisegmental disease where limb salvage was the indication for intervention. Stenosing or recently occluded bypass grafts were successfully dilated in 7 of 8 patients. With a complication rate of 3%, percutaneous angioplasty is clearly a highly effective treatment for lower extremity arterial insufficiency in the properly selected patient judged by immediate and relatively short term follow-up observations.