This paper focuses on inequalities in learning opportunities for individuals coming from different socio-economic backgrounds as a measure of (in)equality of opportunity in OECD countries and provides insights on the potential role played by policies and institutions in shaping countries’ relative positions. Based on harmonised 15-year old students’ achievement data collected at the individual level, the empirical analysis shows that while Nordic European countries exhibit relatively low levels of inequality, continental Europe is characterised by high levels of inequality – in particular of schooling segregation along socio-economic lines – while Anglo-Saxon countries occupy a somewhat intermediate position. Despite the difficulty of properly identifying causal relationship, cross-country regression analysis provides insights on the potential for policies to explain observed differences in equity in education.