New three-dimensional endoanal and endorectal ultrasonographic and magnetic resonance imaging techniques have given better insight into the complex anatomy of the pelvic floor and its pathologic modification in benign anorectal diseases. Obstetrical events leading to fecal incontinence in females, the relationship between fistulous tracks and the sphincter complex, and mechanisms of obstructed defecation syndrome can now be accurately evaluated, which is of fundamental importance for decision making. Thanks to improvements in the diagnosis of these disorders, new forms of treatment have been developed with better outcome for patients. This book is aimed at general and colorectal surgeons, radiologists, gastroenterologists and gynecologists with a special interest in this field. It is also relevant to everyone who wants to improve their understanding of the fundamental principles of pelvic floor disorders.