Prejudice and hate crimes against lesbians and gay men are prevalent throughout the United States. Prejudice in public school settings is particularly problematic for lesbian, gay, and bisexual (LGB) students and LGB parents. Efforts to reduce prejudice for LGB groups have met with limited success. Creating safer and more inclusive school environments is essential. An experimental mixed methods field design tested outcomes of an intergroup dialogue intervention on public school teacher attitudes, feelings, and behaviors toward LGB students and parents. Quantitative results indicate dialogue participation resulted in statistically significant positive changes in attitudes, feelings, and behaviors. Qualitative data analysis confirmed positive changes as a result of dialogue participation.