Although researchers, policymakers, and practitioners alike have long known about the established link between substance abuse and criminal behavior, criminal justice agencies in the United States are still tasked with managing an influx of individuals who display symptoms of abuse and dependence. By the late 1980s, the drug court model emerged as an innovative response to this problem, and this reform has since proliferated to such an extent that it is the most common type of problem-solving court in America. Still, there remains much variation in how drug courts are implemented across jurisdictions, which can have strong implications for the outcomes among the courts’ participants. In this review, we summarize the key research on drug court implementation, followed by an assessment of whether they can be said to “work” in terms of reducing criminal behavior and relapse among adults. We conclude that the model remains an evidence-based practice and suggest some directions for future work, including increased emphasis on theory and causal dynamics and key measurement issues.