Objective: The McKinney-Vento Act (MVA) is the primary federal policy addressing homelessness in America with specific mandates designed to ameliorate the effects homelessness has on educational attainment for school-age children. The extent to which this policy is implemented may have far-reaching effects for homeless children. The MVA Implementation Scale (MVAIS) was developed for the purpose of providing a tool for assessing school-based social services personnel's perceived knowledge and awareness of implementation of the MVA within their service areas. This study tests the factor structure, reliability, and validity of the 26-item instrument. Method: Data were collected from a purposive sample of school social workers (N = 201) attending a Mid-Western regional conference in order to examine the reliability and the validity of this measure. Results: The hypothesized factor structures were confirmed. Findings also indicated high levels of reliability among items, as well as initial evidence of instrument validity. Conclusion: Findings from this study indicate that the MVAIS adequately measures participant's perceived implementation of the MVA. Future implications for research and practice are discussed. (Contains 8 tables.)