Peer group supervision has had little attention in the research literature, although it is a common form of supervision utilised by psychologists in practice. The development and implementation of a structured peer supervision group (PSG) with nine trainee psychologists, within the training setting of university-based services, is described in this study. Audio-recordings of nine hour-long PSG sessions, four individual supervision sessions, a focus group evaluation and individual trainee interviews were gathered, to explore the potential contributions of PSG to a training programme. The data were subjected to a systematic data analytic procedure based on the principles of grounded theory. The findings illustrate a different form of learning experience in PSG, which may complement the learning in dyadic supervision. Strategies which seem to facilitate learning for trainees are derived from a comparison of case material presented in the contexts of both PSG and dyadic supervision. Potential ways of optimising supervision experiences are discussed, and recommendations are made for the further development of the PSG model. (Contains 1 table and 1 figure.)