We studied 425 patients who had undergone radical cystectomy for transitional cell cancer of the bladder and were followed for 5 years or more, or until death. Upper urinary tract urothelial cancer developed in 14 patients (3.3 per cent), 3 of whom had bilateral disease: 2 synchronous and 1 asynchronous. The interval between cystectomy and emergence of the upper tract tumor ranged from 8 to 100 months (mean 40 months). There was a declining incidence of upper tract cancer relative to cystectomy P stage for carcinoma in situ (9.1 per cent), papillary stages O and A (3.6 per cent), stages B1, C and D1 (2.6 per cent) and no residual cancer (0 per cent). Of the 14 patients 8 (57 per cent) had features of multifocal carcinoma in situ in the cystectomy specimens. In 4 of the 14 patients (29 per cent) ipsilateral disease developed when the distal ureteral margins were involved with cancer at cystectomy. Only 3 of the 14 patients (21.4 per cent), all with stage I disease, were alive at the time of this report.