In order to investigate the value of renal revascularization in patients with chronic renal failure and associated occlusive lesions of the renal arteries, the long-term results of 48 revascularizations in 43 patients operated upon between January 1980 and May 1988 were analyzed. There were 36 men and 7 women whose mean age was 61.8 years (range 36 to 79 years). The diagnosis of kidney failure was based on serum creatinine levels greater than 120 micromoles/L on two consecutive determinations. Patients were divided into four groups: Group I (23 patients) had a creatininemia between 120 and 200 mumoles/L, Group II (16 patients) between 200 and 350 mumoles/L, Group III (2 patients) between 350 and 800 mumoles/L and Group IV (2 patients) who had chronic renal failure requiring hemodialysis. Hypertension was found in 37 patients. Renal artery restoration was unilateral in 38 patients, 12 of whom had a solitary kidney. Restoration was bilateral in five patients. In 24 patients, renal artery surgery was associated with reconstruction of the infrarenal aorta. Three patients undergoing associated aortic procedures (7%) died after surgery. Thirty-nine patients were followed for a mean of 35.1 months; one patient was lost to follow-up. Improvement or stabilization of renal function was noted in 24 patients (62%). Deterioration was found in 15 patients (38%), six of whom presently required chronic hemodialysis. In Groups I and II, 69.5% of patients stabilized or improved their kidney function. Renal function worsened in all patients in Groups III and IV. We conclude that restorative renal surgery can improve renal function in patients whose preoperative serum creatinine levels are less than 350 mumoles/L. In this population of patients, associated aortic restoration should be performed only when absolutely necessary.