CODA’s Leadership team

To reach members of our staff, please call our main number, 503-239-8400 or email using the form on our Contact Us page.


Tim Hartnett bioTim Hartnett, MSW, MHA
Executive Director

For more than 35 years, Tim has worked with vulnerable and under-served populations, from incarcerated juveniles to homeless persons suffering from severe and persistent mental illness and substance use disorders. He has worked as a school teacher, direct-service worker, program director, research partner and state policymaker. He serves as an adjunct faculty member at Portland State University’s School of Social Work and is a Visiting Research Fellow in the Queen’s University School of Sociology, Social Policy and Social Work in Belfast, Northern Ireland. Tim joined CODA in 2002 and has served as a member of the Oregon Alcohol and Drug Policy Commission, as president of the Oregon Prevention Education and Recovery Association (OPERA), and as a member of the executive and steering committees of the National Institute on Drug Abuse Clinical Trials Network. Prior to joining CODA, Tim was director of the Division of Alcohol and Drug Abuse Prevention and Recovery for the State of New Hampshire Department of Health and Human Services. He received his Master of Social Work from University of Connecticut and his Master of Health Administration from Suffolk University in Boston.


Eve Klein, MD
Medical Director

Eve has provided clinical services at CODA since 2015, becoming Medical Director in 2016. She also serves as an Instructor in the Comprehensive Adult Neurology Clinic at Oregon Health & Science University where she teaches medical students and treats patients with chronic pain and other neurologic disorders. In addition to her neurology residency, Eve completed pain medicine and addiction medicine fellowships at OHSU. She practiced pain management in the Portland and Vancouver area for four years before joining the field of substance use disorders treatment. She received her undergraduate degree from Columbia University in the City of New York and her medical degree from the University of Massachusetts Medical School.


Alison Noice bioAlison Noice, MA, CADC-III
Deputy Director

Prior to becoming Deputy Director, Alison directed CODA’s Addiction Medicine Program. She has worked exclusively with under-served and indigent populations since moving to Multnomah County in 1999. Prior to joining us in 2010, Alison managed a psychiatric urgent-care clinic, where she worked with high-risk patients and supervised a multidisciplinary team of mental health and medical professionals. She studied Clinical Psychology at University of Montana and received her Master of Counseling from Pacific University. In 2016, Alison received her Graduate Certificate in Healthcare Management from OHSU. Her undergraduate degree is from University of Idaho.





Samanta Byers bio


Samantha Byers
Director of Quality Improvement

Samantha joined CODA in 2014 as Director of Quality Improvement. She previously spent 13 years working in the Child Welfare system, including case management and coordination of a $14 million federal grant for recovery services in the state of Oregon. She received the DHS Director’s Excellence Award for her work coordinating the Family Involvement Team (FIT) project, which brought together Child Welfare, juvenile court and treatment programs. Samantha earned her Bachelor of Arts in History from University of Portland.



Stephen Stephen Cassell
Director of Marketing and Individual Gifts

Stephen joined CODA in 2015, as Director of Marketing and Individual Gifts. During the past 10 years he has provided marketing, event planning and fundraising services to a range of businesses, government agencies and not-for-profit clients. In 2013 Stephen was the recipient of Portland Monthly’s Rising Stars Award, which recognizes individuals who make a meaningful and positive impact in social, political, and business sectors.


Bonnie Holdahl, MBA
Director of Outpatient Services

Bonnie Holdhal bioBonnie joined CODA in 2014 as the Program Director for Outpatient Services. She previously served as Director of Psychiatric Services at LifeWorks NW, and also held management positions in mental health and women’s and reproductive health in the Portland area for more than eight years. Prior to her work in management, Bonnie was a patient advocate and clinic assistant at Planned Parenthood Columbia Willamette. She earned her MBA with a focus on healthcare management from Oregon Health and Science University. Her undergraduate degree is in History.



Eric Knopf bioEric Knopf, MBA
Director of Finance

Eric joined CODA’s accounting department in 2014 before becoming the Director of Finance in 2015. He has provided accounting and financial management services in corporate and small-business settings, most recently including Daimler Truck of North America, Toyota Tsusho America and Erickson Aircrane, all in Greater Portland. He earned his undergraduate degree in History from the University of California, Irvine, and an MBA from George Fox University.





Jill Murray

Jill Murray joined CODA in 2015 as Director of Development. Jill previously served as the Director of Foundation and Corporate Relations at Concordia University. She worked for 14 years advocating for people with intellectual and developmental disabilities, through the OHSU Center on Self-Determination, Portland State University’s Regional Research Institute for Human Services, The Oregon Council on Developmental Disabilities, Oregon Technical Assistance Corporation, and The Arc of Oregon.


Katharina Wiest bioKatharina Wiest, Ph.D., MSPH
Director of Research

Katharina joined CODA in 2007. As Director of Research, she participates as site principal investigator in clinical trials through the Clinical Trials Network of the National Institute on Drug Abuse as well as other academic institutions and organizations. She also provides ongoing, real-time assessment and evaluation of CODA’s population through analyses of the electronic medical records. Katharina received her doctorate in epidemiology from the University of Washington, her Master of Science in Public Health in epidemiology from the University of California-Los Angeles, and her bachelor’s degree in Biology from Pitzer College. She is currently an Affiliate Assistant Professor in the Department of Public Health and Preventive Medicine at Oregon Health & Science University.



Mark McGovernMark McGovern, Ph.D. Mark McGovern consults and advises CODA clinical leadership on the implementation of scientific evidence-based approaches to the assessment and treatment of substance use and mental health problems. Mark is a Professor of Psychiatry and of Community & Family Medicine at the Geisel School of Medicine at Dartmouth. He practices at the Dartmouth Hitchcock Medical Center, and his research program is based at the Dartmouth Psychiatric Research Center. His clinical and research focus is integrated treatment for persons with co-occurring substance use and psychiatric disorders. Since 2009, he has been the Editor-In-Chief for the Journal of Substance Abuse Treatment (JSAT), the leading scientific journal dedicated to addiction treatment research and implementation.




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