Nine months after cadaveric renal transplantation the nephrotic syndrome developed in a patient with insulin-dependent diabetes. Renal biopsy ruled out tissue lesions induced by cyclosporine, chronic rejection, recurrence of diabetic kidney disease and de novo glomerulopathies. Captopril-enhanced nephrography and a high plasma renin response suggested renal artery disease. Angiography revealed five intrarenal arterial stenoses. Four were successfully dilated with a prompt diuretic response and diminished proteinuria. Late angiography showed a moderate restenosis in two of the dilated arteries. Due to persistent proteinuria, elevated blood pressure and higher serum creatinine levels than at nadir after transplantation low-dose ACE inhibitor therapy was started. This normalized proteinuria, blood pressure and serum creatinine levels. This beneficial response to combined renal artery balloon angioplasty and medical treatment has been sustained for 2.5 years.