Arnold Washton , PhD, is an addiction psychologist in private practice at Recovery Options in New York City and Princeton, New Jersey. Specializing in the treatment of alcohol and drug abuse since 1975, he was among the first clinicians to identify the emerging cocaine epidemic in the early 1980s and to establish specialized treatment programs for cocaine abusers. He has served as substance abuse advisor to the U.S. Food and Drug Administration, the White House Office on Drug Abuse Policy, the National Institute on Drug Abuse, the U.S. State Department, professional sports teams, major corporations, foreign governments, and subcommittees of the U.S.

Senate, the U.S. House of Representatives, and the New York State Senate. Joan Ellen Zweben , PhD, is founder and Executive Director of the 14th Street Clinic (1979-2007), and East Bay Community Recovery Project (1989- present), organizations providing comprehensive treatment in Oakland, California. She is committed to providing flexible, evidence-based treatment to challenging and underserved populations. Dr. Zweben is a clinical psychologist with over thirty-five years' experience in treating addiction, and training treatment practitioners. She is the author of 3 books, over 55 articles or book chapters and editor of 15 monographs on treating addiction.

She is a Clinical Professor of Psychiatry at the University of California, San Francisco.