There is a trend in nursing policy and practice towards patients participating actively in their treatments and the services they use. Nursing theorists often attempt to describe the phenomena of patient participation from a psychological perspective while neglecting sociological issues, such as power, ideology and moral status. This paper commences by examining policy and ethical issues in relation to patient participation. Studies examining immediate patient participation, for example active participation in treatments, and distant patient participation, namely participation in psychiatric service planning, are then reviewed. Various settings of psychiatric services are examined, including the initial interview, primary health care, hospitalization and clinical innovation, in order to uncover common themes. These studies often fail to pay attention to the patient's experience of participation, even when clinically innovative schemes are being described, and also fail to develop hypotheses and theories about participation. The importance of a sociological perspective in future studies is indicated. The author concludes that psychiatric patients want a more active role in treatments and service planning, and that psychiatric clinicians, including nurses, find more active patient participation threatening. Nevertheless, there is evidence of more rewarding alliances being formed between patients and nurses in some settings. The nurse's role in democratizing psychiatric services, thus permitting greater patient participation, while fulfilling statutory obligations is a considerable challenge to nursing practice in the future. This paper concludes by discussing some current limitations of nursing research and the value of some ideas taken from critical theory, in particular reflection, dialogue and praxis, as a practical basis for social action and nursing research.