Innovation, a complex concept, underpinned a four-year pan-European research project designed to increase the effective use of technology in school classrooms. This article revisits evaluation data collected during the project and explores the challenges of conceptualising, realising and researching "innovation." The authors describe how innovation was conceptualised, highlighting key issues, not all of which could be resolved in the project. The development of an approach to support teachers to change their practices facilitated the realisation of innovation in the classroom. This approach, through which researchers and national pedagogical coordinators worked with teachers to develop their teaching and learning practices with technology in potentially innovative ways, is outlined. Case study data are then used to exemplify how teachers and other stakeholders applied this approach and how they perceived innovation in practice within their own countries. Through a discussion of these cases, the article highlights the challenge of defining innovation in different country settings and, in turn, the complexity of identifying its occurrence. It concludes by proposing the next steps for similar research endeavours.