Ron Jackson, M.S.W., has served as the Executive Director of Evergreen Treatment Services since 1980. He is a graduate of the University of Washington's School of Social Work, where he currently serves on the faculty as an Affiliate Full Professor.  Under his leadership, ETS has developed a research division that has conducted numerous federally-funded studies of approaches to changing addictive behaviors.  Mr. Jackson is presently the co-principal investigator for community-based treatment programs for the Pacific Northwest Node of NIDA's Clinical Trials Network.  In addition to teaching at the University of Washington, he has lectured throughout the country on topics related to addiction treatment and public health and has published widely in the area of chemical dependency treatment.

Sam Cullison, M.D., a board certified specialist in addiction medicine, has served as the Medical Director of Evergreen Treatment Services since 1978. He is also the Medical Director for Family Medicine Education at the Swedish Health System and Director of the Providence Family Practice Residency Program.  Dr. Cullison is currently President of the Washington State Medical Association and has served as a Clinical Professor of Family Medicine at the University of Washington's School of Medicine since 1987. He has lectured and published extensively on topics related to the medical treatment of addictive disorders and family medical practice.

Betsy Wells, Ph.D., has served as the Director of Research at Evergreen Treatment Services since 1989.  She is also a Research Professor at the University of Washington, School of Social Work.  Dr. Wells has been  the Principal Investigator or Co-Investigator on eleven federally-funded studies on the prevention of HIV among injection drug users and the treatment of substance use disorders. She is currently directing NIDA-funded research projects examining the impact of brief motivational interventions on HIV risk reduction among injection drug users and the process of change in addictive behaviors among stimulant (primarily cocaine) users.   She is also an investigator in the Pacific Northwest node of NIDA's Clinical Trials Network project.  Dr. Wells is the author or co-author of over 30 articles and research reports published in peer-reviewed journals. 

Rachel Diaz, L.Ac., M.S.W., has served as the acupuncture program manager at Evergreen Treatment Services since 1992.  She is currently a member of the Board of Directors of the National Acupuncture Detoxification Association and works as a trainer for that organization.  She also teaches at Bastyr University, the Northwest Institute of Acupuncture and Oriental Medicine, and the Seattle Institute of Acupuncture and Oriental Medicine.

Paul Grekin, M.D., a board certified specialist in addiction psychiatry, has served as the director of psychiatric services at ETS since 1990.  Dr. Grekin is also the Medical Director for ETS' mobile methadone unit and the Medical Director at Seattle Counseling Services. He has been a Clinical Associate Professor of Psychiatry at the University of Washington's School of Medicine since 1990.