Research has shown that offenders committed crimes at much higher rates during periods when they were actively using drugs than during times when they were drug free. The risk of pretrial misconduct could be reduced if defendants who used drugs could be identified at arrest, their release conditioned on the requirement to remain drug free, and their compliance with that condition monitored by mandatory drug testing during the pretrial release period. In Washington D.C., virtually all arrestees are brought to the D.C. Superior Court lockup and tested for the presence of specific drugs in their urine. With the advent of this drug-testing program, a new release alternative became available for drug-using defendants. The defendants can be placed in the Pretrial Services Agency (PSA) of periodic urine testing before trial. Defendants who succeed in the urine testing program can be expected to be better risks for release than those who failed the program. This study's five monographs cover information concerning background and description of the urine-testing program, the views of judicial officers, analysis of drug use among arrestees, the efficacy of using urine-test results in risk classification of arrestees, and periodic urine-testing as a signalling device for pretrial release risk.