Our Team

The MISSION team is made up of leaders in the field of co-occurring disorders (CODs) treatment and research, who are working to increase the effectiveness of COD treatment services across the country. They are committed to improving the lives of the individuals struggling with these disorders.

David Smelson, Psy.D.

David Smelson, Psy.D., is a professor in the Department of Psychiatry at the University of Massachusetts Medical School and research psychologist at the Edith Nourse Rogers Memorial Veterans Hospital in Bedford, Massachusetts.  Dr. Smelson is the developer of the MISSION model. His research on CODs has been funded through the National Institutes of Health, the Department of Veterans Affairs, and the Substance Abuse and Mental Health Services Administration. Dr. Smelson has worked closely with the Department of Veterans' Services, Massachusetts Department of Mental Health and the Massachusetts Department of Public Health to develop, implement, and evaluate a range of services for individuals with co-occurring disorders.


Debra Pinals, M.D., is the medical director of Behavioral Health and Forensic Programs in Michigan. She also has concurrent appointments as a clinical professor in the University of Michigan’s Department of Psychiatry and as the director of the program in Psychiatry, Law and Ethics. Dr. Pinals is the co-developer of the MISSION-Criminal Justice treatment model. She previously worked at the Massachusetts Department of Mental Health, where she oversaw the agency’s justice and behavioral health programs, including juvenile and adult court clinic, mental health court clinical services, police training, and diversion. She also supervised mental health re-entry services and specialized veteran justice programs while providing risk management consultation throughout the agency.  Dr. Pinals also previously served as the interim deputy commissioner of Clinical and Professional Services and interim state medical director of the Massachusetts Department of Mental Health. She has worked on matters related to behavioral and physical health integration with payment reform strategies. In addition, Dr. Pinals was an associate professor of psychiatry and director of the Forensic Education program at the University of Massachusetts Medical School.

Ayorkor Gaba, Psy.D.

Ayorkor Gaba, Psy.D., is a senior project director at the University of Massachusetts Medical School Department of Psychiatry.  Dr. Gaba is a clinical psychologist with expertise in COD assessment, treatment, training and supervision. She currently manages an array of MISSION implementation and program evaluation studies, and serves as the lead in MISSION training development. She has also been actively involved in the development of supplemental materials for MISSION, including toolkits on clinical supervision and family and social support integration. Dr. Gaba has a strong commitment to diversity, global issues, and training. She is an American Psychological Association NGO representative to the United Nations, and has served as a clinical training director in treatment centers focused on instructing doctoral students in the assessment and evidence-based treatment of CODs and trauma.

Jennifer Harter, Ph.D.

Jennifer Harter, Ph.D., is one of the developers of the MISSION model and an author of the MISSION treatment manuals, consumer workbooks and supplementary materials, including a peer specialist and navigator toolkit. Her work focuses on the training of MISSION staff with experience on team-based care and evidenced-based practices. Dr. Harter is also a licensed clinical psychologist skilled in cognitive behavioral interventions and motivational interviewing.

Douglas Ziedonis, M.D., M.P.H.

Douglas Ziedonis, M.D., M.P.H., is the associate vice chancellor for health sciences at the University of California San Diego. He previously served as the chair of the Department of Psychiatry at the University of Massachusetts Medical School and UMass Memorial Medical Center. Dr. Ziedonis is an addiction psychiatrist internationally recognized for his research and leadership in addressing co-occurring mental illness and addiction, particularly to tobacco. He served as an advisor to President Bush’s New Freedom Commission on Mental Health, the President’s Cancer Panel, and the Institute of Medicine's Committee on Gulf War and Health: Smoking Cessation in Military and Veteran Populations. He and his research team have received many National Institutes of Health, Substance Abuse and Mental Health Services Administration, Veteran Affairs, and state research grants.

Elizabeth E. Epstein, Ph.D.

Elizabeth E. Epstein, Ph.D., is a professor of psychiatry at the University of Massachusetts Medical School, and director of the UMass National Center on Homelessness Among Veterans. Dr. Epstein also is a professor emerita of the Center of Alcohol Studies at Rutgers University.  She is the principal investigator and/or co-investigator on several research grants funded by the National Institute on Alcohol Abuse and Alcoholism and National Institute on Drug Abuse. Dr. Epstein also sees patients privately and is a master trainer and clinical training consultant for the Veterans Affairs program to implement evidence-based practices for substance use disorders. Dr. Epstein is the author of Addictions: A Comprehensive Guidebook for Clinicians (Oxford University Press) and two treatment manuals and patient workbooks.

Clinical Research Assistants

Michael Andre, B.A. – College of the Holy Cross

Kathryn E. Bruzios, M.S. – Rivier University

Kelsey Clary, B.A. – Clark University

Pooja Patnaik, B.A. – College of the Holy Cross

Max Trojano, B.A. – College of the Holy Cross

David “Alec” Wierzbicki, B.A. – Duke Univerisity

Past Team Members

Mary Kate Duffy, B.A. – Marketer, Hamptons Lane

Ian Farquhar, B.A. – Research Assistant, Massachusetts General Hospital

Nathan Guevremont, B.A. – J.D. Candidate, Yale Law School

Autumn Harnish, B.A. – Human Ecology P.h.D. Candidate, University of Wisconsin

Rachel Mullins, B.A. – M.S.W. Candidate, Boston University

Kathryn O’Connor, B.A. – Kinesiology P.h.D. Candidate, University of Michigan

Elizabeth Aaker Orvek, M.S., M.B.A. – Database and Application Developer, University of Massachusetts Medical School

Leon Sawh, M.P.H. – Senior Manager, Massachusetts Health Policy Commission

Julianne Siegfriedt, M.A. – Sociology P.h.D. Candidate, University of Massachusetts Boston

Stephanie Singer, M.S. – Clinical Psychology Ph.D./J.D. Candidate, Drexel University

Sigella Vargas – Volunteer Clinical Research Assistant

Roshani Vanmali, B.A. – Clinical Psychology Psy.D. Candidate, La Salle University

Jennifer Vessella, L.C.S.W. – Social Worker, Bedford VA Medical Center

Brittany Walker, B.A. – Regulatory Assistant, Yale Cancer Center

Joining Our Team

To learn more about opportunities to join the MISSION team, please contact us.