Evaluation of anorectal function in faecal incontinence. In cases presenting faecal incontinence, an etiological diagnosis should be based on history, clinical examination, anuscopy and rectoscopy. This diagnosis should be confirmed or contradicted by the results of objective investigations, especially manometry, myography and radiology. In the absence of anorectal anatomical defects, a functional cause of incontinence has to be found: megarectum with pseudo-incontinence, psychogenic encopresis, lesions of the nervous system, pudendal neuropathy. In the presence of obvious anatomical defects, the function of all components of the anorectal continence apparatus has to be evaluated; in this way, it will be possible to objectivate the results of conservative or surgical treatment by repetition of the technical investigations. In practice, a complete functional evaluation of the anorectum has to be performed in patients in whom the results of previous therapy remain unsatisfactory.