The views expressed are those of the authors and should not be attributed to the Urban Institute, its trustees, or its funders. The opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect those of the Department of Justice. Acknowledgments The National Institute of Justice's (NIJ) Multi-Site Adult Drug Court Evaluation (MADCE) entailed multi-site, multi-year process, impact, and cost-benefit data collection, analysis, and reporting that required the collaboration of numerous individuals and organizations to whom we extend our appreciation for their contributions to the successful completion of this study. In particular, we thank the Office of Justice Programs for its support through the Drug Court Discretionary Grant Program, and for other support from the Bureau of Justice Assistance. We also are deeply indebted to the judges, drug court coordinators, and staff of drug courts, as well as the administrators and staff of the comparison jurisdictions, whose efforts form the foundation without which this research would not have been possible: Administrative Office of the Courts for the provision of state-level official records data. We are also grateful to the county jails and state departments of corrections and their staffs that facilitated our ability to perform follow-up survey data collection with respondents who were incarcerated at the time their interviews were scheduled. The authors are solely responsible for any errors in the use of these data. During the course of this study, we had the good fortune to be guided by Janice Munsterman, our initial NIJ technical monitor and subsequently Director of the who ably served as our NIJ technical monitor throughout most years of MADCE. We convened three working group meetings with public and private substantive and technical experts Aside from the authors, many staff of UI, RTI, and CCI supported this effort. We thank Nancy LaVigne, Director of the UI Justice Policy Center, and Terry Dunworth, former center director, for supporting this project from initiation through completion of the final report. We thank D'Orio for their respective contributions in providing data collection, analytic, and administrative assistance to this effort. Lastly, we extend our thanks to the field coordinators and field supervisors, whose dedication to conducting baseline and follow-up interviews was critical to the research effort. Introduction Drug courts emerged spontaneously during the late 1980s and early 1990s in response to burgeoning drug offender arrests and prosecutions that overwhelmed the capacity …