This study examined relationships between perceived heterosexism in high school policies and programs, social environments, and victimization rates among lesbian, gay, bisexual and questioning (LGBQ) students. Secondary analyses of Internet survey data from a large cohort of LGBQ students (N = 2037; 76% male, 82% White; mean age = 16.07; 56% gay or lesbian; 28% bisexual; 16% questioning) yielded moderate correlations between perceptions of non-discrimination and harassment policies, inclusive programs, and the prevalence and tolerance of anti-LGBQ harassment. The perceived availability of inclusive programs was more closely associated with perceptions of the prevalence and tolerance of harassment in schools than were perceived policies. Victimization was related to perceived policies, programs, and harassment. Perceived harassment partially mediated effects of programs on victimization, but perceived programs also predicted victimization even after controlling for perceived harassment. Moderating effects of demographic characteristics (e.g., gender, race, sexual orientation, and outness) were explored.