In 2008, there will be at least 2.5 million new foreclosures in the United States. Record levels of mortgage delinquency, default, and foreclosure are causing widespread hardship in cities and suburbs across America, and causing repeated destabilization of global credit and investment markets. In this Forum, six housing specialists unravel the complex connections between urban geography, subprime lending, and foreclosure. Although a wide variety of view-points are represented, three common threads are evident. First, foreclosures are tightly linked to the lax underwriting standards and aggressive business practices of the subprime mortgage market. Second, the subprime-foreclosure linkage is a reflection of the steady deregulation of U.S. financial markets and the promotion of homeownership as the cornerstone of national housing policy. Third, deregulated mortgage market segmentation has created uneven new geographies of debt, risk, and default—superimposed atop existing landscapes of old-fashioned exclusionary discrimination. Low-income and racially marginalized neighborhoods, once redlined and excluded from mainstream credit markets, were at the center of the profitable wave of subprime abuse and equity extraction during the long housing boom, and are now at the center of the long, slowly unfolding catastrophe of the U.S. foreclosure crisis.