The dissertation examines the functioning of modern forms of prejudice as legitimizing myths within the social dominance theoretical framework, with a particular focus on positive stereotypes and other non-hostilely valenced prejudices. Numerous scholars have suggested that positively-valenced stereotypes and attitudes play an important role in the maintenance and support of social stratification, particularly in the social context when more hostile forms of these prejudices have become increasingly stigmatized. However, little empirical work has been completed to test this supposition and what work has been done has tended to focus on racial and ethnic prejudice. Using ambivalent sexism and modern heterosexism as exemplars, the dissertation finds mixed support for the hypothesis that modern forms of prejudice function as hierarchy-enhancing legitimizing myth as suggested by social dominance theory. The protective paternalism subcomponent of ambivalent sexism, aversive heterosexism, and amnestic heterosexism function, for the most part, in the manner predicted by social dominance theory. However, the gender differentiation and heterosexual intimacy subcomponents of ambivalent sexism, paternalistic heterosexism, and positive stereotypic heterosexism do not. Additionally, the dissertation uncovers a pattern whereby the opposition to equality subdomain of social dominance orientation predicts opposition to ameliorative public policies, but not subdomains of hostile or modern forms of prejudice. Conversely, the group-based dominance subdomain of social dominance orientation predicts subdomains of hostile and modern forms of prejudice, but not opposition to ameliorative public policies.