The Head Start REACH project is taking an in-depth look at the eligibility, recruitment, selection, enrollment, and attendance/retention (ERSEA) approaches that Head Start programs use to engage Head Start—eligible families experiencing adversities. This report summarizes findings from the case studies of Head Start programs, including how Head Start programs identify families most in need of their services; how the programs reach and retain these families; and key themes about the ERSEA approaches that programs use to reach and support them. To understand their ERSEA efforts, we synthesized information from (1) Head Start program staff, (2) families who participate in their programs, (3) organizations the programs partner with to conduct ERSEA work, and (4) Head Start-eligible families not currently enrolled in Head Start. Based on these findings, we provide considerations for practice and potential directions for future research to understand how Head Start can identify and reach families that are most in need of services. (author abstract)