The ‘Conceive-Design-Implement-Operate’ (CDIO) movement of engineering education reform emphasises project-based, experiential learning and the development of professional skills such as teamwork, collaboration and design. As well as disciplinary theoretical knowledge, implementation of the CDIO educational agenda calls for expertise in both engineering design practice and teaching practice. This agenda, it is argued, involves fundamental epistemological and normative shifts and involves engineering educators, like it or not, in what Donald Schon called “the battle of the epistemologies”. This paper situates the CDIO agenda within the wider context of current professional educational thinking. In doing so it argues for the need for engineering education to advert to a third epistemological dimension of reflexivity, beyond theory and practice, now long since embedded in health care, managerial and teacher education. The authors then outline how the reflective dimension has been embedded in the Civil Engineering undergraduate program at the University of Limerick. Examples of both teacher’s and students’ reflections are offered for consideration. Pedagogical practice, approaches to assessment and some challenges encountered in implementing the reflective dimension in an engineering curriculum are outlined.