This study focused on a process and impact evaluation of two long-standing Mental Health Courts (MHCs)that substitute a problem-solving model in place of traditional court processing for defendants with mental illness. Research subjects were drawn from three sources: 1) 648 participants enrolled in the Bronx MHC between January 1, 2002 and December 31, 2006; 2) 327 participants enrolled in the Brooklyn MHC between March 1, 2002 and December 31, 2006; and a pool of approximately 5,000 offenders who were arrested in Brooklyn or the Bronx in 2005-2006 and entered into the Brad H discharge planning database maintained by the Department of Health and Mental Hygiene (DOHMH ). The study found that mental health court participants are significantly less likely to recidivate than similar offenders with mental illness who experience business-as-usual court processing. Individuals who recidivate are more likely to commit drug crimes, than violent, property or other crimes.