This study examined whether school counselors' LGBT-related graduate education and professional development predicted more frequent efforts to support LGBT students, and whether their LGBT-related self-efficacy mediated the relationship between their training experiences and supportive efforts. Results from ordinary least squares (OLS) regression analyses indicated that more exposure to LGBT-related graduate education and professional development predicted more frequent engagement in LGBT-related practices among school counselors. Results from OLS regression-based path analysis further indicated that the direct effect of training on school counselors' practices was partly explained by the positive effects of training on counselors' LGBT-related self-efficacy. The article also discusses the study's implications and limitations.