The presence of an anal fissure is reliably associated with an elevated intra-anal pressure and decreased blood flow to the anoderm. Symptoms include pain, bleeding, pruritus and soiling. Greater than 90% of acute anal fissures are of short duration and heal spontaneously or with simple measures. A high-fibre diet with an increased intake of water is recommended, laxatives may be used when required to soften constipated stool and warm sitz baths may offer symptomatic relief. Acute fissures that fail to heal become chronic fissures, which have traditionally been treated by surgery. This book presents and discusses recent developments on anal fissure conservative medical and surgical treatment, as well as the management of surgical complications.