Seventy-three patients with adenocarcinoma of the sigmoid, rectosigmoid and rectum were reviewed to determine the incidence of suture-line recurrence. Four patients (5.5 per cent) developed suture-line recurrence despite the use of a number of techniques to reduce this problem. All four recurrences were in patients who had Dukes' C lesions of the rectum. It would appear that such recurrences are not related to implantation factors alone.