In conducting the Understanding and Expanding the Reach of Home Visiting (HV-REACH) project, ACF aims to deepen understanding of how home visiting can better reach families, including: (1) families who are not recruited in the first place; (2) families who are recruited for home visiting but do not enroll; (3) families who enroll, but never engage to receive services; and (4) families who are recruited and engage initially, but end their participation early. The project will build knowledge about factors at the participant-, provider-, program-, neighborhood-, and systems-levels that influence identification, recruitment, retention, and engagement of families, for better or worse. HV-REACH is intended to directly benefit home visiting programs by identifying, developing, studying, and disseminating evidence-informed resources and strategies they can implement to ensure more equitable access to and participation of families in home visiting and, ultimately, more positive outcomes for children and families. The project is being conducted by Mathematica in partnership with the Brazelton Touchpoints Center, Social Grove, and the Association of Maternal and Child Health Programs. (author abstract)