The scientist-practitioner model has been widely espoused as the optimum model of professional training and practice for clinical psychologists and increasingly, the related professions of counselling psychology and counselling. However, it has also proved to be contentious regarding the extent to which it reflects or informs the realities of professional practice. This debate has taken on a new meaning in the current health care climate with the increasing emphasis on using research to achieve evidence-based practice'. This study explores clinical psychologists', counselling psychologists' and counsellors' beliefs about the scientist-practitioner model. Key themes relevant to this, and the related areas of theory, research and clinical formulation, were identified through in-depth, qualitative interviews and then tested further by using a survey instrument devised to reflect these themes. The results suggested differences between the professional groups in beliefs about research and the scientist-practitioner model and also indicated the influence of work setting. Differences in idiosyncratic definition of the scientist-practitioner model also emerged, which appeared to be related to beliefs about its value. Implications for training and professional practice are discussed and the contribution of the study to the existing literature and wider debate are reviewed.