The author engages in a lengthy review of the empirical literature concerning the treatment of mentally ill offenders, particularly focusing on three main studies. The methodologies and findings of these studies are discussed. Then the author proposes a new study to determine the effectiveness of Assertive Community Treatment (ACT) programs in reducing the recidivism rate among mentally ill offenders. In the proposed study, the researcher uses a pre-test, post-test longitudinal design over a 24-month period to exam 185 respondents housed in the local jail. All 185 respondents will be selected based on a diagnosis of mental illness. It was suggested that approximately 20 respondents will enter an ACT program, while the remaining 165 respondents will serve as a control group (no treatment). Regression analysis should be conducted to examine the relationships between criminality, mental illness, substance abuse, and other variables. Using a time-series design, the respondents will be followed for a 24-month period to measure recidivism rates within that time period. Limitations of the proposed study include the lack of a true experimental study because of human subjects concerns and the inconsistency of data available in public data records. The appendices of the article contain sample questionnaires for the proposed study. References