School-Wide Positive Behavior Interventions and Supports is a framework that aims to improve school culture and climate, students' behavior and attendance. As the program is largely spreading, comparative studies showing its efficacy on students' outside the United States are needed. In addition, there is a need for studies examining SWPBIS effects on school climate from all the stakeholders' point of view, especially students and parents. Moreover, few researches used comprehensive questionnaires including the three main components of school climate: engagement, safety and environment. The purpose of this study is twofold: investigate the SWPBIS implementation feasibility in a French speaking European country and measure implementation effects on school climate and absenteeism. Using a quasi-experimental design, the current study investigates the impact of SWPBIS implementation in elementary and secondary high-need schools (n intervention schools = 4, n control schools = 5). Findings show positive effects for all stakeholders on different components of school climate. Effects on absenteeism are mixed. Implications and limitations are discussed.