Objectives-Intravesical chemotherapy has been studied in randomized clinical trials for >30 yr; however, the optimal schedule and duration of treatment are unknown. The objective is to determine the effect of schedule and duration of intravesical chemotherapy on recurrence in patients with stage Ta T1 bladder cancer.Methods-A systematic review was conducted of the published results of randomized clinical trials that compared intravesical instillations with respect to their number, frequency, timing, duration, dose, or dose intensity.