To date in Alberta, over 750 teachers in 250 schools have been trained in the Fourth R program, with reach to over 45,000 youth. While reach goals have been successful, the process of scaling this program in such a large geographical area had led to questions about factors influencing implementation quality within the Alberta context. In particular, quantitative and qualitative data collected over the past five years indicate that many teachers struggle to implement the program with high fidelity. Because of this, project partners were interested in understanding factors that influence implementation quality among teachers in Alberta. Pilot data collected in 2015-16 from eleven teachers indicated an association between higher implementation quality and more positive perceptions of evidence-based programs, as well as associations between higher implementation quality and school climate. As such, measures tapping the presence of caring adults; perceived levels of administrator support; support for and coordination of school programs; and perceptions of evidence-based programs have been rolled out to province-wide implementation monitoring for 2016-17 (anticipated N=130). We will present findings from analyses that explore how differences in school climate (including at the school and administrator levels), support for programs, and perceptions of evidence-based programs predict both implementation quality as well as barriers to high-quality implementation. This study will also be the first to present data on teacher perceptions of school climate across Alberta, which is important to the design of pre-service education and professional development activities. Implications for how findings highlight the need for comprehensive approaches to the scale-up of evidence-based interventions will also be discussed.