Zach Walsh, PhD, is a clinical psychologist and an Associate Professor of Psychology at the University of British Columbia, where he directs the Therapeutic Recreational and Problematic Substance Use lab. He has published and presented widely on topics related to cannabis, psychedelics, mental health and psychotherapy. He is the lead investigator for several ongoing studies of the therapeutic use of cannabis including a clinical trial of cannabis for PTSD. Zach was also a member of the clinical team for the Vancouver arm of the MAPS-funded study of MDMA-assisted psychotherapy for the treatment of Post Traumatic Stress Disorder. Zach’s clinical focus is on the application of “third wave” mindfulness-based behavior therapies to address trauma, relationship conflict, and problematic substance use.