Stephanie Marquesano, an Ardsley, New York resident, is a passionate advocate, educator, and innovator in the field of co-occurring disorders (COD)—the intersection of mental health challenges and substance misuse. After the death of her 19-year-old son, Harris, to an accidental overdose in 2013, Stephanie founded The Harris Project Inc., the only nonprofit in the U.S. dedicated to developing a system of care to better serve individuals with, or at risk of developing, COD. Through her work, she advances evidence-based, integrated treatment models like Encompass and created CODA (Co-Occurring Disorders Awareness), a peer-led prevention initiative that educates, empowers and connects youth, families, and communities to critical resources.
Stephanie serves on the New York State Opioid Settlement Fund Advisory Board, advocating for innovative funding strategies to address COD. She helped create the first co-occurring disorders prevention curriculum in collaboration with the Partnership to End Addiction, Westchester County, and key coalitions, school districts and faith leaders, supported by local opioid settlement funds. She also helps coordinate a multi-year federal Substance Abuse Mental Health Services Administration grant that expands access to integrated treatment for young people and their families using Encompass and the Invitation To Change approach.
Her work includes groundbreaking public awareness efforts, such as the award-winning “You Don’t Know The Half Of It” campaign developed with Havas New York, which has received more than 40 national and international awards for its impactful messaging.
Stephanie has been recognized for her efforts locally, across New York State, and nationally. Harris’s story and her work were featured in The New York Times Sunday Review opinion piece, “Experts Say We Have the Tools to Fight Addiction. So Why Are More Americans Overdosing Than Ever?” and she delivered a TED Talk at the National Council for Mental Wellbeing Conference in May 2023.
A graduate of Brooklyn College (BA, Political Science and Public Communication) and New York University School of Law (JD), Stephanie’s leadership continues to reshape prevention, treatment, and recovery across the continuum.