The proposed project will focus on the experiences of LGBTQ students, namely students who are lesbian, gay, or bisexual (LGB), who have a gender identity that is different from their biological sex (Transgender), who refuse traditional notions of dichotomous identities, e.g., female-male or heterosexual-LGB (Queer), or who question their sexual identity (Questioning). Research demonstrates that LGBTQ youth are more vulnerable to compromised mental health and school achievement because of experienced minority stressors at school (i.e., experiencing or expecting discrimination, concealing, and internalizing anti-LGBTQ prejudice). The proposed project will conduct the first cross-national study to assess minority stressors, mental health and school achievement among LGBTQ students from countries of the European Union (six confirmed to participate). The objectives are 1) To examine the minority stressors associated with LGBTQ students’ characteristics and experiences; 2) To determine how school and community characteristics influence the school climate and minority stressors; 3) To cross-nationally compare the experiences of LGBTQ youth. For this purpose, we will merge student reports with independent information at the school and community levels. The proposed project will be the first empirical application of a social-ecological model to fully understand LGBTQ mental health and school achievement disparities. Research and practice implications are discussed.