Despite America’s reputation as the land of opportunity, more than 16 million (1 in 5) American children live below the poverty line. To break the cycle of poverty, we must find ways to intervene early and adopt a two-generation approach that helps both parents and children excel, rather than merely survive. Good behavioural design can help families derive maximum benefit from the resources and services available to them. This report shares behavioural insights on the many challenges facing families with low incomes and those who seek to support them. It suggests key design principles that follow from these insights and can be tailored to fit the needs of a wide range of communities, organizations, policies and programs.