According to social-identity theory (Tajfel and Turner, 1986), persons desire positive self-esteem, and their self-esteem is tied inextricably to the way their in-group is evaluated relative to other groups. Social groups or categories not only systematize the world, they also provide a system of orientation for self-reference; they create and define the individual's place in society. "Out-groups" are any social group with which individuals compare their own in-group to assess it and thus make judgments about themselves. According to Tajfel and Turner, differentiation of the in-group from an out-group both fosters and is generated by group conflict. Social-identity theory can help explain why lesbians and gay men are especially likely to be victims of hate-motivated violence. As a group generally held in low regard by society, lesbians and gay men are likely to represent a relevant out-group for all quarters of society, particularly for persons lower in the social system. This paper also identifies the limitations of social-identity theory in explaining discrimination against homosexuals and suggests implications of social-identity theory for the prevention of discrimination and hate toward homosexuals. 3 notes and 20 references