Surveys were distributed to 263 operating adult drug courts, and 81 percent responded. Results clearly indicated that treatment services designed for and used by drug courts comported with scientifically established principles of treatment effectiveness. Overall, the structure of drug court treatment was consistent with principles established by the National Institute on Drug Abuse. Most drug courts reported that they included adjudicated offenders in their target populations, either exclusively or in addition to diverting low-level and first-time offenders from further criminal justice processing. Adult drug court participants included both felony and misdemeanor offenders, as well as offenders with drug charges, drug-related offenses, and probation violations. More than 60 percent of drug courts reported they excluded participants with minimal substance involvement and they reserved drug court slots for participants whose substance abuse and related criminal activity was severe enough to warrant significant interventions. More than 27 percent of drug courts had fewer than 50 participants in their programs, 42 percent had between 50 and 150 participants, and 31 percent had more than 150 participants. Most drug courts reported having access to residential (92 percent), intensive outpatient (93 percent), and regular outpatient (85 percent) treatment, and almost all drug courts encouraged or required participation in self-help activities such as Alcoholics Anonymous or Narcotics Anonymous. A significant proportion of drug courts (58 percent) said they were able to provide culturally competent programming, and 77 percent said gender-specific and women-only programming was available. Support services were also available to drug courts, including mental health treatment, educational remediation, vocational training, and relapse prevention. The greatest frustrations described by drug courts included limited access to residential treatment and specialized services for women, minorities, and the mentally ill. Drug courts had fairly informal relationships with both dedicated and external providers, and screening and clinical assessments were routinely conducted to identify drug court participant needs. Drug courts experienced a variety of difficulties related to engaging and retaining clients in treatment. Policy implications of the survey findings are discussed in the context of further improvements to drug court treatment services. 4 references and 2 figures