This article contributes to the literature on parental self-sufficiency and child well-being in two ways. First, we bring a novel interdisciplinary perspective to formulating hypotheses about the pathways by which policy-induced changes in the environments in which children are embedded, both within and outside the home, facilitate or harm children’s development. These hypotheses help to organize the contradictory assertions regarding child impacts that have surrounded the debate over welfare reform. Second, we draw on a set of policy experiments to understand the effects of reforms targeting parents’ self-sufficiency on both parents and their children. The random-assignment design of these evaluations provides an unusually strong basis for identifying conditions under which policy-induced increases in employment among low-income and mostly single parents can help or hurt young children’s achievement. (Author introduction)