There were 104 major complications (13.1%) and 34 deaths (5.9%) among 502 patients with evidence of renovascular disease who underwent 577 operative procedures. The operative mortality rate in patients with atherosclerotic renovascular disease was 9.3% vs 3.4% with fibromuscular hyperplasia. Important determinants of renovascular operative mortality are (1) cause of disease, (2) presence of coronary artery disease, (3) presence of bilateral renal functional impairment, (4) the complexity of the renal operative procedure, and (5) concurrent extrarenal surgery.