Twenty patients with advanced transitional cell carcinoma of the bladder were treated with radiation and concomitant continuous infusion of 5-fluorouracil with or without Mitomycin. Nineteen of 20 patients were assessed for response. Fourteen of 19 patients (74%) obtained a complete response within 3 to 6 months. An additional three patients (15%) acquired and maintained a complete response after local transurethral resection of the tumor and intravesical chemotherapy, raising the overall complete response (CR) rate to 17/19 (89%). Of the two patients with persistent disease, one is alive and well after salvage cystectomy. Eighteen of 20 patients were evaluated for survival with a median follow-up of 38 months. Seven patients remain alive and well 51 to 78 months, whereas three patients died from intercurrent disease. Eight patients died of either distant metastatic disease (7 patients) or regional disease (1 patient). An adjusted survival calculated by the Life Table Method was 53.6% at 5 years, whereas the overall survival was 39%. The combined modality therapy was well tolerated with no need for treatment interruption or reduction in dose. Late bladder complications include one patient with hemorrhagic cystitis, two patients with dysuria, and two with symptoms of irritable bladder. One patient required a colostomy for a chronic hemorrhagic proctitis. Bladder preservation was achieved in 19/20 patients.