Using a retrospective, quasiexperimental design, this study evaluates Minnesota's Challenge Incarceration Program (CIP), examining whether it has lowered recidivism and saved money. In addition to utilizing a lengthy follow-up period and multiple measures of recidivism and participation, a multistage sampling design was employed to create a control group that was not significantly different from the CIP group with respect to control variables. The results reveal that although CIP significantly reduced the time to reoffense, it did not have a significant effect when recidivism was measured as any return to prison. CIP reduced costs through a recidivism reduction, however, because when CIP offenders returned to prison, they stayed 40 fewer days than control group offenders because they were less likely to return for a new crime. Overall, the analyses show that CIP has saved Minnesota at least $6.2 million by providing early release to program graduates and reducing the time they later spend in prison. (Contains 8 tables and 11 notes.)