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Justin Castello


Dr. Justin Castello, a licensed clinical psychologist, was born and raised in the CA central bay area. He earned his Bachelor's in Psychology at the University of California Santa Cruz and his Ph.D. in Clinical Psychology at the California School of Professional Psychology in San Francisco (SF). He has worked in the mental health field for over 17 years and as a Harm Reduction Psychotherapist for 14 years, in a variety of settings.

This work began in a locked acute psychiatric facility and in social rehabilitation housing in Santa Cruz. In his 9 years with the Harm Reduction Therapy Center (HRTC) he provided therapy at a community program for transitional aged youth in the SF Haight, at two community programs in the SF Tenderloin, at Pretrial Diversion of SF County, at a K-8 charter school for at-risk youth in east Oakland, and at HRTC’s SF and Oakland private practice offices as Program/Intake Coordinator. In January 2016 he joined UC Berkeley University Health Services (UHS) Social Services Unit as part of their Alcohol and Other Drugs and Trauma Teams, and has been honored to collaborate with UHS staff to support and serve its students.

In addition to his therapeutic role, he’s provided trainings and presented on Alcohol and other Drugs, Harm Reduction Therapy, Harm Reduction Group Facilitation, and other psychological issues at UHS and on campus, at the Harm Reduction Coalition in Oakland, at the Harm Reduction Conference in New Orleans, at the American Psychological Association Convention in Hawaii, and at American Group Psychotherapy Association Conferences in New York. He is also a UC Berkeley and UC San Diego Extension Instructor and for multiple semesters has taught a course on Substance Use Treatment and Group Facilitation.