The need for more affordable rental housing is on the rise, but so are the costs to develop that housing. In September 2012, Enterprise Community Partners and the Urban Land Institute’s Terwilliger Center for Housing launched a joint research effort to examine the various factors affecting the cost of developing affordable rental housing. The research team convened roundtable discussions in five cities Chicago, Denver, Los Angeles, New York City, and San Francisco—to explore the issue of cost. Additional interviews were held with an array of practitioners, developers, and financiers.