Results of disease-oriented phase II trials with cis-dichlorodiammineplatinum(II) (cis-platinum) in 135 adequately treated patients with advanced urothelial tumors at Memorial Sloan-Kettering Cancer Center are presented. In four protocols which used cis-platinum alone or in combination with Adriamycin and/or cyclophosphamide in 95 patients with bladder cancer, no significant difference (46%--54%) in the number of partial remissions (PRs) in previously untreated patients was noted. The median duration of response in three of the four protocols was 5--7 months. A review of the literature indicates that cis-platinum used singly produced remissions in 45% of 67 patients (95% confidence limit, 12%--57%). In the treatment of superficial bladder tumors, intravesically administered cis-platinum induced few complete or sustained remissions. The difficulties in evaluating response with intravesical therapy are discussed. The importance of patient selection, particularly the need to include patients with objectively measurable disease parameters, in phase II trials is stressed. Differences in patient characteristics and response criteria will necessitate prospective randomized trials of cis-platinum alone versus cis-platinum combination regimens in the treatment of metastatic disease. cis-Platinum was inactive (12% PRs) in 25 patients with prostatic cancer who had objectively measurable parameters. It is of interest that PRs were obtained in three of six patients (50%) with penile cancer. A review of the literature and the data in the present series indicates that cis-platinum has no value in the treatment of metastatic hypernephroma.