Using organizational neo-institutionalism as a framework, our theoretical study argues that the existing literature on immigrants’ educational failure has to be expanded by examining school’s key role. Dominant explanations of immigrants’ educational failure focus on their lack of resources (“deficit” explanations) or on the selectivity of national educational systems favouring (higher class) majority students. In our approach, we argue that, even in institutional environments discouraging ethnic minority students’ inclusion, schools, as agents, maintain leeway in shaping their policies and practices towards multicultural student populations. We conclude the paper by presenting the research design for our empirical study and presenting the Flemish educational system on which it will focus.