The research I am conducting is part of the European SILNE-R project. Within this project, my study aim is to develop a comprehensive understanding of what constitutes the effectiveness of prevention programmes implemented at the school level (e.g. smoking bans). This process of developing understanding follows a Realist Approach, indicating it fundamentally builds on a realist philosophy of science and therefore focuses on interactive patterns in contexts, mechanisms and outcomes. In all, the objective is to better understand and address the different responses to tobacco interventions.