Eighteen patients with recurrent and/or multifocal superficial transitional cell carcinoma of the bladder who were rendered tumor-free by transurethral resection and were then treated with either a single or second six-week course of induction Bacillus Calmette-Guerin (BCG) therapy, followed by maintenance therapy, were retrospectively reviewed. A 73 percent complete response rate was achieved in those patients treated prophylactically, while a 70 percent complete response rate was observed in patients treated for carcinoma in situ (CIS) with an average follow-up of twenty-nine months. Maintenance therapy may be warranted in those patients able to tolerate it without significant side effects.