Twenty-six patients with renal vascular hypertension were treated with percutaneous transluminal dilatation. Twenty-one were followed for more than 1 year; 18 underwent repeat angiography. Recurrence of stenosis was shown angiographically in one of six patients with fibromuscular disease and in 12 of 12 patients with atherosclerotic disease. The procedure was more likely to result in cure of hypertension (six of 10) in patients with fibromuscular disease than in patients with atherosclerotic disease (one of 16). Although percutaneous transluminal angioplasty provides the advantages of simplicity, reduced cost, and probably reduced risk, long-term utility of the procedure remains to be established. A prospective randomized trial, establishment of a registry, or both would serve this purpose.