This sequential mixed methods study evaluated the impact of the Chicago Parent Program (CPP) in 12 Baltimore Title I PreK programs on parent engagement and student outcomes from kindergarten through 2nd grade. Phase 1 (quasi-experiment; N = 11,996) compared PreK students whose parents enrolled in CPP with those whose parents did not enroll in CPP on measures of kindergarten readiness, chronic absenteeism, suspensions/expulsions, and grade retention. Phase 2 (qualitative; n = 20) explored the perceptions of school-based staff, principals, and district and community leaders on CPP's impact on parents, students, and parent engagement, and why they sought to continue CPP in the schools. Research Findings: No effects on student outcomes were found using administrative data. However, all of those interviewed described observed improvements in parent and student behavior and parent engagement and all schools have continued implementing CPP. Practice or Policy: Qualitative results highlight the importance of stakeholder perspectives and the limitations of administrative data for evaluating brief interventions serving families with complex needs.