Despite important progress in psychiatry not all patients respond well to available treatments. There are also concerns about increasing costs and the quality of the therapeutic relationship, which seems threatened by managed care, focus on protocols, and a tendency to reductionism, narrowing the view to diseases or symptoms and losing sight of the whole person in his or her context. ‘Integrative medicine’ is a new concept in health care defined as: ‘the practice of medicine that reaffirms the importance of the relationship between practitioner and patient, focuses on the whole person, is informed by evidence, and makes use of all appropriate therapeutic approaches, healthcare professionals and disciplines to achieve optimal health and healing’. Integrative medicine may provide some solutions to the problems raised. However, there is a paucity of research on the application of integrative medicine in mental health care (‘integrative psychiatry’). We explored the conceptual foundation of integrative psychiatry in the first part of this thesis. The second part is about its implementation in Dutch mental health care. Taking into account the Dutch law, jurisprudence, rules of professional bodies, and scientific research, we wrote a treatment protocol for the judicious application of complementary medicine in conventional mental health care. In the third part we assessed evidence for the effectiveness of integrative psychiatry and some selected complementary medicines and lifestyle changes. In the discussion we respond to criticism and offer suggestions for future research.