Inclusionary housing policies are local land use policies that link approvals for marketrate housing to the creation of affordable homes for low- and moderate-income households. The primary goals of inclusionary housing programs are to expand the supply of affordable housing and promote social and economic integration. The ability to not only produce affordable homes, but also to ensure their long-term affordability, is critical for meeting the housing needs of the lower-income families and individuals that inclusionary housing programs aim to serve. Even as inclusionary housing programs have become more prevalent, there is a lack of information on successful strategies for facilitating lasting affordability. This paper analyzes a set of 20 inclusionary housing programs to highlight how long affordability periods, strong legal mechanisms, carefully designed resale formulas, dedicated program stewardship, and strategic partnerships can help preserve affordable homes produced through inclusionary housing programs for multiple generations. In addition, this research describes initial findings from a first-of-its-kind, national directory of local inclusionary housing programs.