Millions of children worldwide are under legal guardianship of the state, often due to abuse, neglect, parental death or other circumstances—leaving governments to determine how best to care for them. The Bucharest Early Intervention Project has shed light on ways to improve the quality of caregiving for children. Initiated in 2000, the BEIP is a randomized controlled trial of foster care as an alternative to institutional care for children who experienced severe psychosocial deprivation.