In post-conflict and divided societies, global citizenship education has been described as a central element of peacebuilding education, whereby critical pedagogy is seen as a tool to advance students' thinking, transform their views and promote democratic behaviours. The present study investigates understandings of and attitudes to global citizenship and the challenges faced in its implementation. Teacher interviews highlight lack of time and resources for critical reflection and dialogue. Where opportunities for relevant training are provided, this can benefit critical engagement. Boundaries of educational systems and structures also influence pupils' understandings of the issues as evidenced in questionnaire findings. We argue that critical pedagogies may be limited unless criticality and activism transcend local and global issues and are applied to schools themselves. Emotional engagement may be required for teachers to claim the space to critically reflect and share with colleagues within and beyond their sectors in order to enable critical discourse amongst pupils.