An account is given of 5 anal and 36 colorectal cancers occurring in Nigerians of the Igbo ethnic group. The rectum was the site of predilection for colorectal growths, and most rectal growths occurred in males. In contrast to the situation in the Western world the disease is rare, affects relatively younger patients, and is often advanced at presentation. Dietary factors probably play no significant role in the aetiology of the disease.