&NA;A retrospective analysis was undertaken of 51 patients with primary anal canal carcinoma who were treated by radiation therapy, with surgery being reserved for those with residual carcinoma. The five‐year uncorrected survival rate was 59 per cent, and the corrected survival rate was 71 per cent. The primary tumor was controlled by radiation alone in 29 of 51 patients (57 per cent) and by subsequent radical surgery in eight of ten patients. Abnormal lymph nodes were controlled by radiation alone in eight of 11 patients. Only three of 29 patients required surgery for complications associated with radiation in the absence of persistent tumor. Seventy‐seven per cent (23 of 30) of long‐term survivors did not require colostomy and retained anal continence. It is concluded that modern radiation therapy techniques are well tolerated and are an effective method of treating carcinoma of the anal canal.