This paper reports on findings from a comparative sociological study of ‘international mindedness' in the IB's Diploma Programme in India, China and Australia. The study focused on the ways in which students, parents and teachers in six IB school-communities in these countries interpreted conceptual constructs under the umbrella notion of ‘international mindedness'. These constructs included Multilingualism, Intercultural Understanding, Global Engagement and other concepts deliberated on and developed by participants through their lived experiences, including constructs shaped through participants' religious philosophies, their social and political contexts, and through cultural and linguistic references. This paper explores the ways in which these expanded understandings of international mindedness are negotiated through the curriculum, pedagogy and assessment practices of schools across the three national contexts. We also examine how contemporary international education can balance both the interdependence of global issues and cultural differences. The study makes an important methodological contribution to the global sociology of schooling by positioning research participants as theorists and foregrounding ‘conceptualisation' (i.e. theorising) as a normal feature of their intellectual work. Understanding participants' conceptualisations (categories, images and metaphors) of their internationally-oriented education offers new insights into local and contextualized accounts of what it means to be a ‘global' citizen.