Workplace-Based Assessment (WBA) plays a pivotal role in present-day competency-based medical curricula. Validity in WBA mainly depends on how stakeholders (e.g. clinical supervisors and learners) use the assessments-rather than on the intrinsic qualities of instruments and methods. Current research on assessment in clinical contexts seems to imply that variable behaviours during performance assessment of both assessors and learners may well reflect their respective beliefs and perspectives towards WBA. We therefore performed a Q methodological study to explore perspectives underlying stakeholders' behaviours in WBA in a postgraduate medical training program. Five different perspectives on performance assessment were extracted: Agency, Mutu...