He completed his study medicine in 1976, and completed the specialization as a psychiatrist in 1982. In addition, he is widely trained in psychotherapeutic streams, and is a member of the Cognitive and Behavioral Therapy Association. Initially, he worked as a general psychiatrist in Psychiatric Hospital 'Endegeest', and later in the GGZ Bulb Region and the GGZ Leiden, departments of social psychiatry. Since 1992, he has also been associated with Pharos health care for refugees. From 1999, he is a psychiatrist, a principal outpatient and researcher at the outpatient clinic and day clinic of Centrum '45 in Oegstgeest, the national center for the treatment of victims of extreme violence. In addition, he was eleven years deputy psychotherapist for the training of physician assistants psychiatry. He has his own practice for psychiatry and psychotherapy, with particular treatment of anxiety disorders and depression, and as a specialization of highly gifted issues. He is also specialized in diagnostics and treatment of traumatized refugees. He is one of the founders of the Department of Transcultural Psychiatry of the Dutch Association for Psychiatry in 2001. He has been Secretary of this Section for more than seven years. He was also a member of the Dutch Scientific Activities Committee for the Netherlands Association for Psychiatry for more than six years. He has been a member of the Board of Psychotherapy since 2007 and since 2012 board member and treasurer of the Psychotherapy Department of the Netherlands Association for Psychiatry. Since 2009 he has been a board member, and later chairman of the Transcultural Section of the World Psychiatric Association. Currently he is the Honorary Advisor of this Section. In 2014, he was appointed Honorary Member of the World Psychiatric Association in thanks for the energy he has put into the Section. He is co-editor of the international magazine Transcultural Psychiatry, and reviewer of many international magazines. His list of publications includes more than 90 articles, books and bookships, on transcultural psychiatry, refugees and traumatic stress. His field of research concerns transcultural diagnostics and somatization for refugees and migrants.