OBJECTIVE We compare the perioperative and long-term morbidity of a cohort of patients who had undergone Studer ileal neobladder urinary diversion with that of a similar cohort who had undergone ileal conduit urinary diversion during the same interval and by the same surgeons. METHODS Between 1990 and 1996 we performed Studer ileal neobladder urinary diversion in 62 men and 4 women, and ileal conduit urinary diversion in 66 men. Mean age of the neobladder and conduit patients was 62 and 69 years, and mean followup was 17 and 20 months, respectively. RESULTS Of 66 neobladder cases (18%) 12 had a total of 16 perioperative complications and a 5% reoperation rate, whereas 12 of 66 conduit cases (18%) had a total of 17 perioperative complications and a 6% reoperation rate. Mean hospital stay was 13 days for each group. Of the neobladder cases 14 (21%) had 14 late complications and an 11% reoperation rate, whereas 8 conduit cases (12%) had 9 late complications and an 8% reoperation rate. CONCLUSIONS The Studer ileal neobladder urinary diversion is a safe procedure with perioperative and long-term morbidity comparable to ileal conduit diversion at our institution.