Considerable activity has occurred in the recent past regarding policy-making around Education for Sustainable Development (ESD) in the school curriculum. Teaching about sustainable development involves complex and contested ethical and political issues. This case study research investigates how four student teachers taking part in a one-year teacher education programme in a university in England (Post Graduate Certificate in Education or PGCE) translate their knowledge, experiences and beliefs about ESD into classroom practice in the context of the Geography National Curriculum and ESD policies in secondary schools. The researchers critically analyse curriculum materials used by three student teachers to explore the potential for ethical and political engagement with ESD knowledge. The research reveals some of the ethical and political dilemmas faced by student teachers who, as committed environmentalists, struggle to resolve the tensions between the constraints of policy, school culture, school teaching materials and their own values and enthusiasms. (Contains 4 notes.)