Education is an important component of peacebuilding in divided societies. Northern Ireland is one such society emerging from conflict yet it retains a divided system of education with 'Protestants' and 'Catholics' generally educated separately. This causes duplication of provision with settlements having to cater for both communities, leaving schools smaller than they could be, and raising questions of sustainability. It also segregates children. This paper analyses Geographic Information to identify and quantify duplication in provision at primary level, building on earlier research. Results show a lack of improvement in levels of duplication in Northern Ireland's primary education over a 5-year period, despite multiple school closures during this time designed to address sustainability within a tight education budget. There is even some suggestion that levels of duplication, and thus waste, are increasing. This is important in terms of planning for education provision to address the future needs of parents and children in Northern Ireland and may have wider relevance to other societies dealing with divided education systems.