ACE inhibitor challenged renal scintigraphic studies offer noninvasive means of evaluating patients for renovascular hypertension, and provide help in selecting patients who will benefit most from interventional procedures designed for alleviation of renal artery stenosis. These studies provide functional assessment of each kidney which also helps the vascular surgeons to plan which renal artery to repair first, when bilateral renal arteries are stenotic, prior to an abdominal aortic aneurysm repair. Vasotec challenged Tc99mMAG3 renal scintigraphy is one of such tests with several advantages over other similar methods, and appears to have a great potential of being a preferred scintigraphic study for evaluation of renovascular hypertension.