The act required the Director of the Administrative Office of the U.S. Courts to establish a program of mandatory drug testing of criminal defendants in eight Federal judicial districts. The program began January 1, 1989. To the extent feasible, drug testing was to be completed prior to the defendant's initial appearance before a judge or magistrate judge. The results of the test were to be included in the pretrial services report presented to the judicial officers. The legislation further provided that, for felony offenses, a mandatory condition of probation or supervised release be no illegal use of any controlled substances and submission to periodic drug tests for use of controlled substances at least once every 60 days. Of the various on-site testing methodologies available, the Probation and Pretrial Services Division selected the immunoassay technique. The initial screen performed was the same for pretrial services defendants at all sites. The initial screen tested for the presence of six drugs: amphetamines, benzodiazepines, cannabinoids, cocaine, opiates, and phencyclidine. In the pretrial phase, any positive results were retested on the on-site equipment prior to the defendant's initial appearance. In the postconviction phase, all initial screens and confirmations were performed by the contractor. Statistical results presented from the pretrial phase address defendants who refused to participate, drugs identified, tests for persons released on pretrial services supervision, and the effects of drug testing on pretrial release and detention rates. Other data pertain to demographic characteristics of defendants who participated in initial appearance testing and the postconviction phase of the demonstration project. Conclusions from the data are presented. 7 tables