The rectum is the ending portion of the large intestine, which terminates in the anus. This chapter discusses various anorectal diseases, their signs and symptoms and the different diagnostics methods to correctly diagnose the ailments associated with the rectum and the anus. The most common ailments include hemorrhoids, anal fissures, perianal abscess, and anal fistulas. Bleeding is the first and most important symptom of hemorrhoids. Initially, it is slight, bright red and occurs during defecation. A mucoid discharge is noticed when the piles are prolapsed and the mucosa is exposed. The discharge leads to pruritus due to irritation of the skin. Pain is generally absent in hemorrhoids unless strangulation or thrombosis has occurred. The anal fissure is often associated with a movement of hard stool or prolonged diarrhea. Hard fecoliths gives rise to stretching of the anal canal and splits the anoderm. An acute anal fissure is followed by severe spasm of the internal sphincter with little inflammatory reaction. A swelling will be present lateral to anal opening (perianal abscess) or in ischiorectal space (ischiorectal abscess). A fistula in ano is a track lined by granulation tissue that opens internally into the anal canal or rectum, and externally onto the skin around the anus.