Marie Nyswander was the co-discoverer of methadone maintenance. In the 1960s she and Vincent Dole carried out clinical trials and established the first officially sanctioned methadone clinics, which became models for maintenance programs throughout the world. In 1967 she and Dole theorized that heroin addicts had undergone a permanent metabolic change. They needed narcotics in a visceral way, which explained why abstinence was not a realistic goal-a claim that remains hotly disputed. Nyswander's work in the 1960s marked an abrupt shift in her thinking about addiction. Her previous approach had been centered on psychoanalysis. Her embrace of methadone maintenance and the metabolic theory amounted to an intellectual conversion. Nyswander was prepared for that conversion by years of patient relapse; she was frustrated with orthodox therapy. At the same time the success of such drugs as chlorpromazine suggested that psychiatric disorders might yield more readily to chemotherapy than talking therapy. Her own heavy smoking may have led her to question whether addiction was a psychiatric disorder in the first place. Finally, Nyswander had a long history of self-reinvention, having previously changed her politics, her medical specialty, and even her name. She was temperamentally suited for a conversion experience.