The majority of infections begin in an anal crypt and its gland. - About 90% of idiopathic perianal abscesses occur because of infection of the cryptoglobular glands. Most occur posteriorly and in the intersphincteric space, where the anal glands are located. - Abscesses are classified as *superficial* or *deep* in relation to the anal sphincter. If the infection bursts through the external sphincter, it will form an *ischiorectal abscess*. - Ischiorectal abscesses are usually confined deep but inferior to the levator ani muscle. - Carcinoma of adjacent organs should be considered with fistulous abscesses. - Perianal abscesses are the most common form of anorectal abscess not pilonidal abscess. Gent/flagyl/amoxicillin or 2g Cef3