Friedemann Pfafflin, M.D., Ph.D., is Professor of Psychotherapy and head of the Forensic Psychotherapy Unit at Ulm University, Germany. Trained as a psychiatrist at Hamburg University, he first engaged in transgender clinical work in the mid-1970s when he visited the Psychohormonal Research Unit and the Gender Identity Clinic at The Johns Hopkins University Clinic in Baltimore, Maryland. From 1978 to 1992, he worked at the Institute of Sex Research at Hamburg University, Germany, and continued the work with transsexuals after moving to Ulm University in 1992. His main areas of research are transsexualism, transgenderism, psychotherapy process research, forensic psychiatry and psychotherapy, and history of psychiatry. From 1995 to 1997, he was President of the Harry Benjamin International Gender Dysphoria Association, Inc. Together with Eli Coleman, he founded The International Journal of Transgenderism in 1997. In 2003 he Co-authored the book Transgenderism and Intersexuality in Childhood and Adolescence together with Peggy T. Cohen-Kettenis, Ph.D.

Peggy T. Cohen-Kettenis, Ph.D., is a Dutch Professor of Medical Psychology at the Free University Medical Center in Amsterdam. She was a pre- and postgraduate student in developmental and clinical psychology at the University of Utrecht. She was trained to become a registered clinical psychologist and psychotherapist at the Utrecht Institute for Multidisciplinary Psychotherapy. After completing her Ph.D. thesis, she worked at the Department of Clinical Psychology of the Utrecht University. There, she conducted a study evaluating sex reassignment, promoted by the advice of a committee of the Health Council, the medical advisory board of the Ministry of Public Health. The outcome of this study would also be the groundwork for a new law allowing transsexuals to adjust their birth certificates. In 1987, she started the first outpatient clinic in Europe for children and adolescents with gender problems and intersex conditions. In September 2002, she became the Professor of Medical Psychology at the Free University Medical Center in Amsterdam. She is the head of a gender clinic for children, adolescents, and adults. Her main areas of research are gender identity problems and gender-related psychopathology.

In 2003 she published the book "Transgenderism and Intersexuality in Childhood and Adolescence" together with Friedemann Pfäfflin.

Ira Hebold Haraldsen, M.D., is the president of the G.I.D. – Clinic at the Norwegian state hospital. She was educated MD at the university in Bonn, Germany in 1985. Ira Haraldsen began working with transsexuals clients in Norway in 1995. Ira Haraldsen is a member of the institute of the psychotherapy in Norway. Thanks to her important work the options of treatment for transsexuals are much better today than ever before at the state hospital, Rikshospitalet.
Ira Haraldsen and her team works closely together with the LFTS.

Esben Esther P. Benestad, MD., is educated MD at the university in Oslo. Esben Esther (EE) is a member of the HBIGDA since 1996. EE is a specialist in clinical sexology NACS and an assistant professor at the Agder University College in the South of Norway. In addition she/he has fulfilled course in systemic therapy IAP. Since April of 2004 she/he is a member of the board at LFTS. EE har worked with transgendered people since the late 1970`ties, is an important specialist for transgender people in Norway and works continuously to improve the options of treatment and support for transe-people. E E is especially engaged in the treatment for children and adolescents with gender problems. Together with specialist in clinical psychology and spesialist in clinical sexology NACS Elsa Almås, EE has published several books on sexology and gender. Her/his latest contribution is a booklet called "Transekjønn og diagnoser" ("Transgenderisms and diagnoses")