This report presents examples of national, statewide, and local research on the recidivism rates of drug court participants. Such research has shown that drug court participants and graduates have a lower rate of recidivism than similar offenders who have not participated in drug courts. Research on the cost-effectiveness of drug courts conducted at the State and local levels shows that the comparatively lower rates of recidivism for drug court participants make them more cost-effective for dealing with drug problems than either probation or prison. Research has also shown that drug courts, through their coercive monitoring of treatment attendance and progress, are a more effective structure for maintaining participation in involuntary drug treatment than other mechanisms used in the past. Other problems currently being addressed in the courts by using the drug court model include juvenile delinquency, child abuse, neglect and permanency, impaired driving, mental illness, homelessness, domestic violence, prostitution, and community reentry from custody. The results of the National Survey on Problem Solving Courts compiled in January 2004 indicate that the expansion of these problem solving courts is well underway in every State. This report concludes with brief descriptions of the structure and operations of 11 types of problem solving courts. Tables on the number and type of operational problem solving court programs in each State as of December 2003 and drug court legislation and State appropriations by State, a list of survey participants, 50 references, and 7 notes