Methadone Anonymous (MA) is a new 12-step fellowship developed for methadone maintained heroin addicts. A total of 53 MA members completed a survey assessing factors related to methadone maintenance treatment program (MMTP) entry, drug use, MA participation, beliefs concerning effectiveness of MMTP and MA, and level of social cohesiveness. Length of time in MA was associated with a decreased use of alcohol, cocaine, and marijuana. Clients rated components of MA to be significantly more helpful to recovery than MMTP treatment components. Affiliation to five MA members known best by the respondents was significantly greater than affiliation to non-MA members. Length of time in MA was positively associated with MA affiliation. Social affiliation and endorsement of 12-step principles were positively correlated. These findings suggest that MA participation has benefits not available in professionally driven MMTP, and should be further studied.