Nine patients with Wegener's granulomatosis have developed chronic renal failure and undergone chronic hemodialysis and transplantation. These patients are all young (less than 43 years); all except one are male. They present with acute renal failure that resolves with hemodialysis and immunosuppression, but then slowly develop chronic renal failure in spite of adequate immunosuppression. On chronic dialysis no manifestations of Wegener's granulomatosis occur despite low or no immunosuppression in most of them. After transplantation the usual post-transplant immunosuppression regimen (azathioprine and prednisone) not only prevents rejection, but also controls the disease. In only one patient has it been necessary to change from azathioprine to cyclophosphamide because of recurrence.