During the last ten years the authors treated 462 bladder tumors of 319 patients in the expectation of radicality. On the basis of histopathological examination following TURs with differenciating technique the tumor-removing proved true in the cases of 360 tumors (78%). The first TUR was radical only in 65% of the tumors, in 10% the second, in 2% the third and in 1% the fourth intervention resulted full radicality. The authors analyse the number of TUR's needed to complete removing of tumors in connection with the depth of infiltration and the configuration of tumors. The exploration of the causes of failure makes possible the improvement of the results.