This study evaluated whether engagement (i.e., attendance and quality of participation) in the Parenting our Children to Excellence (PACE) program predicted positive child and parent outcomes. PACE in an 8-week preventive intervention aimed at parents of preschool children. The study investigated the relation of engagement to outcomes in an ethnically diverse sample of 610 parents and among a subset of those parents at high risk for child maltreatment. Overall results demonstrated that engagement in PACE significantly improved child and parent outcomes at post-assessment and/or one-year follow-up assessment. Results for the high-risk subsample were even stronger as engagement significantly improved almost all of the child and parent outcomes at post-assessment, which continued to significantly improve in the year following program completion. Findings provide support for the efficacy of PACE in improving child and parent outcomes in an ethnically diverse community population and among parents considered at risk for child maltreatment.