What is the role of knowledge in the Recognition of Prior Learning (RPL) in Higher Education? This paper presents the findings of empirical research at a Canadian university. A position of knowledge differentiation located in a social realist sociology of knowledge is adopted. This is not an obvious or usual position for scholars of RPL, because it holds that what distinguishes formal academic knowledge from experiential knowledge is a question of the structure and purpose of the knowledge. Research into a range of academic and professional education programmes points to degrees of--and different types of--possible connection between formal and experiential knowledge. Findings offer an indication of the type of programmes in relation to which the implementation of RPL is likely to be most feasible. Additionally, findings show how social factors other than knowledge types enable or constrain the implementation of RPL. Avenues for further research are suggested.