Increasingly higher education programs are made learner centred and flexible to face societal changes. Challenge-based learning (CBL) is an educational concept shaping these open and flexible programs. This article aims to articulate a framework for analysing CBL characteristics within and between study components in academic curricula. It contributes to a detailed conceptualisation of CBL and clarity on what CBL implementations consist of. The dimensions and indicators of the framework reflect points of attention for research and evaluation of CBL design and implementation. We argue for variety in CBL characteristics between study components or curricula. Furthermore, we point out how this conceptualisation of CBL opens for research into designing and teaching for multiple domains, and how it contributes to an identification of commonly agreed characteristics of CBL. Recent CBL projects are referenced as an illustration of the approach. The detailed conceptualisation informs debate and development in a nascent field of research.