In this retrospective study 119 patients with T1-T4 carcinoma of the urinary bladder were treated with split-course radiotherapy. The 3-week rest period was compensated with a 10% increase in the total radiation dose to 6600 cGy. Therapy was completed as planned by 86% of the patients. The actuarial 5-year survival for these patients was 20%. Both the 3- and 5-year survival figures were better for patients with local control of the tumour achieved either by combined surgery and radiotherapy or by radiotherapy alone, than for patients with recurrent tumours after radiotherapy. The results of the split-course regimen were comparable to the results of continuous radiotherapy used for urinary bladder cancer.