During the experiment, all drug felony defendants were randomly assigned to one of three dockets established to expedite the handling of drug cases. One drug-case docket intervened in the standard manner. Another docket intervened through a new comprehensive treatment program. The third offered an experimental program that mandated a graduated schedule of sanctions if the defendant failed compulsory drug tests. Researchers measured the impact of the programs on defendants' drug use, criminal activity, and social and economic functioning, using court records and self-report data from a survey of defendants. The study also examined program costs and estimated the value of benefits in the form of averted costs of victimization, arrest, prosecution, and incarceration. The evaluation found that sanctions program participants were significantly less likely than the standard docket sample to be arrested in the year following sentencing. Assignment to dockets offering the experimental programs significantly reduced defendants' drug use during pretrial release. The reductions in drug use were even greater when programs participants were compared to the standard docket. Sanctions program participants who attended Narcotics Anonymous/Alcoholics Anonymous during the program period had a significantly lower likelihood of heroin and/or cocaine use in the year after sentencing. Treatment program participants reported significantly fewer drug-related social problems than standard docket participants in the year after sentencing. The significant reductions in arrests among sanctions program participants resulted in a total net benefit of $713,570, which amounted to savings of approximately $2 for every $1 in program costs. 5 exhibits