Eighty-nine male patients underwent cystoprostatectomy for bladder carcinoma. Prophylactic urethrectomy was performed only on 7 patients whose tumour extended to or beyond the bladder neck. During the follow-up period 9 of 82 patients (11%) developed a urethral recurrence. Eight out of these 9 patients had carcinoma in situ or multiple papillary tumours in the bladder. Of all those patients who had carcinoma in situ, either primary or concomitant with papillary tumour, 18% developed urethral recurrence. The corresponding figure for patients with multiple tumours in the bladder was 15%. Thus the presence of carcinoma in situ or multiple tumours in the bladder seem to be important risk factors for urethral recurrence after cystoprostatectomy.