Reported rates of tumour response for metastatic bladder cancer vary widely among different institutions, even when similar drug regimens are employed. These differences are due to selection of patients, quality of supportive care, and to methodological differences in the design, analysis and reporting of clinical trials. Because of these factors, intercomparison of response rates from different phase 2 trials is not very meaningful. Trials from the Princess Margaret Hospital have demonstrated palliation from several regimens, but it remains uncertain whether aggressive regimens using several drugs are superior to less toxic chemotherapy. Current clinical trials which randomize patients to receive aggressive chemotherapy or single agents should help to resolve some of these problems.