An increasingly important treatment group is the expanding population of methamphetamine-using female offenders. This study focused on women methamphetamine-using offenders (n = 359) who were treated either in a modified therapeutic community (TC) program ("Clean Lifestyle is Freedom Forever" [CLIFF]-TC: n = 234) designed for non-violent offenders with significant impairment from methamphetamine use, or the standard outpatient (OTP) treatment (OTP: n = 125). All participants were assessed on motivation, psychological and social functioning, and treatment engagement before and during treatment. A multilevel repeated measures analysis examined changes between intake and end of Phase 2 treatment. Both CLIFF-TC and the traditional OTP treatments were shown to improve psychosocial functioning, with significant changes on measures of self esteem, depression, anxiety, decision making, hostility, risk taking, and criminal thinking errors. Effect size comparisons indicated treatment gains were larger in the CLIFF-TC than in the OTP group. Both groups rated treatment engagement measures of participation, satisfaction, and counselor rapport to be very high. These results have positive implications for managing and improving treatment of methamphetamine-using women offenders because psychological improvements during treatment have been linked to better post release outcomes. (Contains 1 table.)