This article situates international expatriate schools in their cultural and political economy by drawing attention to the tensions between a cosmopolitan educational ethos and processes of social, economic and legal enclavement. Based on extensive multi-sited ethnographic research in the international school sector, we show how cosmopolitan claims of openness mirror a relative closure and ‘offshore-like’ enclavement. To do so, we build upon the notions of modularity and extractivism, which we use as heuristics to analyse social and spatial practices of defining boundaries. Gazing beyond the main foundational myth of international schools, we first outline their concomitant extractive roots. Second, we shed light on the conditions of international teachers’ circulation worldwide. Third, we examine the territorial entanglements and disentanglements that characterise international schools. Finally, we investigate the tensions induced by a cosmopolitan educational ethos whose discourse of inclusion is inevitably paired with practices of exclusion.