In tabulating the results of this analysis, subjects were divided into three cohorts of varying length of time in treatment in order to accurately compare pre- and post-treatment arrest rates. The results showed that methadone maintenance treatment for drug abuse can effectively reduce criminal behavior among patients in treatment. Pre-admission arrest histories showed that the subjects were on an upward spiral at the time of their application, and that this trend continued during the waiting period prior to admission. Secondly, the patients committed considerably more crimes during this pre-admission period than had been reported for patients in several other methadone maintenance treatment programs in the city. All these figures are made even more significant by the extremely high rate of retention, up to 80 percent, of methadone maintenance programs. 6 figures and 3 notes