Social dominance orientation (SDO) is a personality trait measuring an individual's support for social hierarchy and the extent to which they desire their in-group be superior to out-groups. SDO is conceptualized under social dominance theory as a measure of individual differences in levels of group-based discrimination; that is, it is a measure of an individual's preference for hierarchy within any social system and the domination over lower-status groups. It is a predisposition toward anti-egalitarianism within and between groups.