Mr. Marion is Executive Director of the Division of Substance Abuse, Department of Psychiatry and Behavioral Sciences of the Albert Einstein College of Medicine. He has been at Einstein since 1970 and has held Executive level positions in the Division since 1977. Prior to his tenure at Einstein, Mr. Marion earned a Master's Degree from the City University of New York, while concurrently teaching in New York City public schools. While working at Einstein, he pursued doctoral studies in public health at Columbia University.

Throughout his career, Mr. Marion has provided consultation and leadership for many professional organizations, advisory boards and committees. He has served as a member of the New York State Governor's Substance Abuse Advisory Council and the Governor's Advisory Council on Alcoholism and Substance Abuse. In 2004, Mr. Marion was awarded the Governor's Lifetime Achievement Award for outstanding service to the field of addiction treatment in New York State. He is a Member of the Board of Directors and Past President of the Association of Alcoholism and Substance Abuse Providers (ASAP) of New York State, where he is presently Public Policy Co-Chair. Mr. Marion also currently serves as President of the Board of Directors of the New York State Committee of Methadone Program Administrators (COMPA), of which he has been an ongoing Executive Board Member since 1974, and is a Member of the Board of the American Association for the Treatment of Opioid Dependence (AATOD). He is Co-Chair of the Center for Substance Abuse Treatment's (CSAT) Consensus Panel on Medication Assisted Treatment, a consultant to CSAT's National Leadership Institute and is Co-Editor of the Journal of Maintenance in the Addictions, published by Haworth Press.