Primary adenocarcinoma of the small intestine is an uncommon tumour, the incidence being 40-60 times less frequent than carcinoma of the colon. Multiple primary neoplasia of the small bowel, although not infrequently seen with benign growths, is an extremely rare event with malignant lesions. A patient is described who had an adenocarcinoma of the duodenum and jejunum, with a previous history of colonic carcinomas. The case is discussed together with a brief review of the literature.