Purpose:: To evaluate (a) long-term survival and (b) the incidence and nature of long-term morbidity/ mortality related to chemoradiation using the anal cancer experience. Methods and Materials: : From January 1979 to April 1987, 34 consecutive patients with Stage I (5 patients), II (15 patients), and III (14 patients) canters of the anal canal were treated definitively with a chemoradiation regimen combining 41.4 Gy pelvic radiotherapy with two concurrent cycles of 5-fluorouracil and mitomycin C, Cumulative actuarial survival was calculated at 10 years and long-term morbidity was categorized per RTOG/EORTC late toxicity criteria, Specific criteria to grade anal toxicity were devised. Results:: Cumulative survival for all 34 patients was 92% at 5 years and 85% at 10 years, The most frequent late toxicity was chronic diarrhea in 17 (50%) patients, Five patients (15%) had Grade 3 or 4 late toxicities, Sexual dysfunction was present in 2 of 26 evaluable patients (7%). Conclusions:: Excellent long-term survival and colostomy-free survival is possible for anal cancer patients treated definitively by chemoradiation, Late effects do not appear to be frequent or intense enough to deter the use of chemoradiation in anal cancer. The biologically expected increase in long-term toxicity when combining radiotherapy and chemotherapy is not substantiated by the results of this study.