A perusal of the literature or of statistics relative to malignancy of the bladder inevitably leaves the reviewer with three major impressions: (1) the lack of a uniformity in the classification of tumors of the bladder; (2) the variety of methods employed in their treatment, and (3) the depressingly poor results obtained. Improvement in classification is essential before the value of any method of treatment can be determined. It is obvious that no deductions of value are possible so long as various investigators report their cases under entirely different classifications. Not until a uniform nomenclature has been adopted can the best type of treatment be selected and the final results from such treatment improve. The present confusion with regard to classification is best appreciated after a review of some of the recent reports on malignancy of the bladder. Kidd1refers to simple papillomas, inflammatory papillomas, true papillomas, simple primary