Defining self-injurious behavior (SIB) presents some difficulties. It has been broadly defined as behavior that produces injury to the individual’s own body (Tate & Baroff, 1966a), and thus could be seen as including suicide, self-neglect, substance abuse, malingering, and so forth—all terms that infer some intent on the part of the client. The research literature on modification of SIB, however, has settled on a narrower definition: overt acts directed toward oneself that have restricted spatial and temporal topographies, whose rate of occurrence is reliably observable, and whose consequences are actual or threatened physical damage. Even this definition is not satisfactory, though. S. R. Schroeder, Mulick, and Rojahn (1980) have pointed out that it suffers from three flaws: (1) the consequences specified by the term do not pertain functionally to the reinforcing stimuli responsible for maintaining the behaviors; (2) researchers disagree about the membership of various topographies in the response class of SIB; and (3) no single intervention strategy is indicated for the particular “class” of SIB as opposed to other behaviors.