It seems reasonable to define abnormal sexual behavior as behavior that is uncomfortable for the person, inefficient, bizarre, or physically or psychologically harmful to the person or others. The american psychiatric association defines paraphilias as recurrent, intense, sexually arousing fantasies, urges, or behaviors that are obsessive and compulsive. Four theoretical approaches have been used in understanding the paraphilias: learning theory, cognitive theory, the sexual addiction model, and sociological theory. Several explanations have been proposed for the fact that there are many more male than female paraphiliacs. A fetishist is a person who becomes erotically attached to some object other than another human being. Most likely, fetishism arises from conditioning, and it provides a good example of the continuum from normal to abnormal behavior. The transvestite derives sexual satisfaction from dressing as a member of the other gender. Like many other sexual variations, transvestism is much more common among men than among women.