Psychologist-in-Chief, Centre for Addiction and Mental Health (2001-2014)
Director of Training, APA-CPA Clinical Psychology Internship Programme, Clarke Institute of Psychiatry (1994-2000)
Chair, DSM-5 Work Group on Sexual and Gender Identity Disorders, American Psychiatric Association (2007-2013)
Committee Member, DSM-IV Subcommittee on Gender Identity Disorder of Childhood and Transsexualism (1989-1994)
Participant in Work Group to Revise DSM-III, Gender Identity Disorder of Childhood and Transsexualism (New York State Psychiatric Institute, New York, New York, April 23, 1985)
Consultant, Somatic Psychic Work Group, Task Force on Coding for Mental Health in Children, American Academy of Pediatrics (1992-1996)
Member, Task Force on Gender Identity, Gender Variance, and Intersex Conditions, American Psychological Association (June 2005-2008)
Past President, International Academy of Sex Research (2006)
Editor, Archives of Sexual Behavior (2002-Present)
Book Review Editor, Archives of Sexual Behavior (1988-2001)
