Residential segregation of America’s neighborhoods by income has been increasing over the past 40 years, with nearly 9 million people now living in census tracts with poverty rates of 40 percent or more (Watson, 2009, Kneebone, Nadeau, and Berube, 2011). Because housing policy affects the geographic concentration of poverty in a variety of ways, policymakers have long been concerned about the possibility that living in a distressed neighborhood could have some harmful effects on the life outcomes of adults and children. The list of plausible reasons why neighborhood poverty might adversely affect people’s well-being and behavior is long and includes limited exposure to peers and role models who support pro-social behaviors such as schooling and work, neighbors who are willing and able to cooperate and work together to improve community life, high-quality local public institutions such as schools, police, health care and housing, and elevated exposure to risk factors like pollution or crime (...).