Dr. Barrett is the Director of the Clinical Support Unit at the Cambridge Police Department and an Assistant Professor of Psychology in the Department of Psychiatry (part-time) at Harvard Medical School. He is the former Director of School-Based Programs in the Division of Child/Adolescent Psychiatry at the Cambridge Health Alliance.  Dr. Barrett is the author and developer of the Fight Navigator curriculum under the Eleanor and Miles Shore Fellowship from the Harvard Medical School to address retaliatory violence in youth.  Dr. Barrett has presented at numerous national conferences on juvenile justice, gang violence, juvenile safety assessment, preventing retaliatory violence, and police-mental health partnerships.  He has contributed to national meetings convened by SAMHSA, the MacArthur Foundation and the International Association of Chiefs of Police.  He is a contributor to Translational Issues in Psychological Science, the Journal of Applied Juvenile Justice Services, Psychological Services, Adolescent Psychiatry, The Community Psychologist, and The Handbook of Human Development for Health Professionals.