Mainstreaming Education for Sustainable Development in higher education is vital if graduates are to possess the abilities, skills, and knowledge needed to tackle the sustainability issues of the future. In this article we explain the development and piloting of a baselining tool, the Education for Sustainable Development and Global Citizenship Development Framework, developed with support from the Higher Education Funding Council for Wales. We draw comparisons with the Sustainability, Tracking, Assessment and Rating System Program, developed by the North American Association for the Advancement of Sustainability in Higher Education. The resulting framework offers consistency with existing Welsh Government strategic documentation, builds on increasing momentum, and has relevance across the higher education sector globally.