Self-injury is defined as behavior that results in tissue damage and is thus defined by its effects rather than topography. Common forms of self-injury include head banging, face slapping, biting of hands and arms, and banging head and/or limbs against objects. Less common forms include eye poking, inserting fingers or objects in body orifices, pica, rumination, skin picking, and aerophagia. Many but not all forms of self-injury are repetitious. Self-injury can be distinguished from stereotyped behavior because of the lack of tissue damage associated with the latter. Self-injury can also be distinguished from self-harm, which consists of deliberate self-cutting and self-burning. Self-harm is often practiced by individuals with borderline personality and eating disorders and is associated with emotional regulation. This entry examines several factors regarding ...