The Eco-Schools programme in South Africa is the longest-running Education for Sustainable Development (ESD) initiative in Africa, which aims to enhance environmental literacy amongst students. This paper reports on a qualitative study involving a focus group of environmental educators working for a non-profit organisation. Through a Rapid Appraisal Method, the environmental educators identified 44 successful eco-schools along with criteria and indicators which typified their selections. A Google search for articles on eco-schools found narrative histories of environmental learning to validate the indicators with a reflective commentary. The research identified 16 indicators including the 'award' achieved by schools, a supportive principal, an eco-committee, sustained eco-projects and whole-school involvement. This study develops and tentatively proposes a set of indicators that could support 'successful' ESD practice in South African contexts. It provides a critique of these context-specific indicators and recommends that we should use them as a reflective rather than a standardisation tool.