This is the first published study of its kind in an Irish context, offering combined insights into the status and practice of Development Education in post-primary schools as well as an interrogation of how development issues are represented in the formal curriculum. It adopted a qualitative approach, enabling a rich description of what Development Education looks like in an Irish context and how it is understood in post-primary schools, as well as an in-depth exploration of teachers’ experiences and views about ‘doing’ Development Education in post-primary settings. Combining an analysis of curriculum materials (including 75 lesson plans and a similar number of textbooks) as well as in-depth interviews with 26 in-career teachers currently teaching Development Education in a broad and diverse cross-section of post-primary schools, the study provides a comprehensive portrait of Global Citizenship Education in Irish second-level schools.