At its construction in St. Louis in 1951, Pruitt-Igoe was hailed as a model for future public housing efforts, but within two decades the area had decayed into an impoverished, crime-ridden neighborhood. By 1976, the entire complex was demolished. What caused this housing project to fail so spectacularly, and how can contemporary architects avoid the same mistakes? Susanne Cowan, a post-doctoral fellow in architecture and history at Washington University in St. Louis, discusses the legacy of these buildings and the evolution of social design. Cowan, with Ayda Melika, co-produced the forthcoming documentary film Design as a Social Act.