While family reunification is the primary permanency objective for children who must be placed temporarily outside of their homes, reunification is not possible for all children. For those children who do not return to their parents and cannot find permanent homes with other family members, adoption is the favored outcome. This review examines the composite measure in the federal Child and Family Services Review that measures agency performance related to the timeliness of adoptions of foster children. It summarizes the multiple factors that research has found to be associated with increased risk for adoption delay and disruption. These include child characteristics, family of origin and adoptive family characteristics, and features of child welfare services and systems. Practices that have been broadly linked to adoption timeliness or address risk factors associated with delays in adoption are described, including social worker activities and agency or system-wide practice.