In a retrospective study of 198 patients with transitional cell carcinoma of the upper urinary tract, post-operative recurrences developed as contralateral tumours in 2.5%, in the ureteric stump after conservative resection in 19% and in the bladder in 36.4%. Upper tract recurrences resembled the primary tumours in terms of grade and stage; of the bladder tumours, 89% were similar in grade and 72% similar in stage to the primary tumours. Age, sex, grade and stage had no effect on the number of bladder recurrences, but ureteric tumours had significantly more recurrences than renal pelvicaliceal tumours. Sex, bladder recurrences and site of primary tumours did not influence survival. Thus grade and stage of the primary tumour were the only predictive variables of the final outcome.