The Homelessness Research Institute published a report written by Jill Khadduri of Abt Associates. that reviewed a series of studies that indicated that housing vouchers are successful in helping families exit homelessness and can protect poor families from becoming homeless. The idea that adequate amounts of affordable rental housing would prevent and end family homelessness is intuitive. It is also firmly grounded in the research literature on the causes of homelessness and on the efficacy of programs that seek to end homelessness for individual families. This paper summarizes those research findings and draws out their implications for housing policymakers on all levels of government – in the first instance, for the federal government, which carries the responsibility for adequately funding the Housing Choice Voucher Program and for setting the parameters for the use of those housing subsidies.