Renal artery stenosis (RAS) can accelerate or generate progressive hypertension and renal dysfunction. The goals for treating patients with RAS are to reduce cardiovascular morbidity and mortality attributable to elevated arterial pressure and to preserve renal function beyond critical stenosis. Recent, randomized trials with current antihypertensive agents indicate that many patients with RAS can be managed for years without renal artery revascularization. As it does elsewhere, atherosclerotic disease can progress to more severe occlusion in the renal arteries. Rapid advances in endovascular techniques, including stenting, make restoration of renal blood flow possible in more patients than before. Therapeutic goals are achieved by 1) avoidance of tobacco, 2) reducing arterial pressure with antihypertensive drug therapy, particularly those agents capable of blocking the renin-angiotensin system, and 3) renal revascularization, using balloon angioplasty and stent placement, surgical bypass, or endarterectomy. The major clinical challenges are to identify progressive occlusive disease and to determine appropriate timing for vascular intervention.