There are numerous sustainability challenges facing the world today, including: climate change, pollution, consumerism and poverty. To make the world a more sustainable and better place to live in, humanity needs to be able to generate solutions to increasingly complex, and ever growing global sustainability challenges. Education is an important vehicle in this respect, in that it can be used to re-orient perspectives and attitudes of learners towards sustainability, motivating learners to seek to transform themselves and society, and thus promote actions for sustainability. In Ireland, despite various initiatives from the turn of the 21st century, the integration of sustainability in academic programmes within higher education has remained largely unchanged. Educators within higher education in Ireland and elsewhere need specific guidance on how best to integrate and/ or infuse sustainability in their programmes and courses of study. This research set out to do this – thus, it explored how sustainability might be integrated/ infused in higher education, with a particular focus on identifying the key sustainability themes, principles, pedagogic practices and specific competencies that should underpin a model for infusing sustainability in higher education, while also investigating how the effectiveness or otherwise of particular competencies (developed within a sustainability-infusion curriculum process) might be evaluated at a meta-level. This mixed methods research study focused on the Irish context, primarily researching and analysing developments within Dublin City University, which was engaged in the reorientation of its curricula towards sustainability in the EU Tempus RUCAS project from 2010-2013. The outcomes of this study have resulted in the design and development of the Green Curriculum Model, a conceptual-design framework for educators to re-orient curricula towards sustainability. The research also resulted in the design, development and evaluation of a sustainability competencies assessment tool called the Dispositions, Abilities and Behaviours (DAB) Framework for profiling learners’ sustainability competencies across higher education faculties, programmes and courses.