Turcot's syndrome represents the association between familial multiple polyposis coli and neural tumors. The syndrome is reviewed with reference to genetics, colonic and central nervous system manifestations. This evidence suggests that Turcot's syndrome represents one manifestation of the pleiotropic autosomal dominant gene responsible for familial polyposis coli and the associated extracolonic manifestations of Gardner's syndrome. A diagnosis of Turcot's syndrome should be restricted to those patients with familial polyposis coli associated with gliomas or medulloblastomas. A further case is presented that is believed to be the first report of such a case in the United Kingdom.