Renal artery stenosis may be caused by either atherosclerosis or fibromuscular dysplasia, and is responsible for hypertension or renal failure. Universal screening of all hypertensive patients is not recommended because of the relatively low prevalence of the disease. A selective approach is needed. The detection of renal artery stenosis requires noninvasive tests with a high predictive value (Doppler ultrasonography, intravenous angiography, spiral CT angiography, captopril renography) in patients in whom hypertension is severe, refractory to therapy, or associated with progressive renal insufficiency. Yet, after such screening, arteriography remains the gold standard of detecting and quantifying renal artery stenosis.