There were studied 130 patients with Ta, T1 and T2 transitional cell carcinomas of the urinary bladder, all treated by transurethral resection. After transurethral resection the follow-up was performed in 48 cases by cystoscopy and urine cytology and in 82 cases by cytology alone. In the first group there were 27 recurrences; cystoscopy failed to identify recurrences in 3 cases and cytology in one of them; all 3 patients with apparently false positive cytology recurred at 4, 9 and 11 months from the cytodiagnosis. From 82 patients of the second group 42 developed recurrences. Urine cytology was positive in 80.9%, suspect in 14.2% and false negative in 4.7% of cases. There were only 2 unsuspected recurrences with a consecutive delay in the correct diagnosis of recurrence in another one. Our results suggest that urine cytology can replace cystoscopy only when it exists a good correlation between its results with pathological findings (over 80% real positive results).