This case study focuses on the involvement of service users in learning and teaching about assessment and the context in which this occurs at the University of Glasgow. One of a number of methods of assessment taught to social work students is person centred planning. Learning takes place through students participating in a series of exercises which can be used in person centred planning. In the final session, John, a service user, was introduced to the class and he explained how person centred planning had helped him take control of various aspects of his life. While this was a positive experience for both John and the students, the need for careful preparation prior to bringing service users into the classroom is essential.