Housing Policy Debate • Volume 9, Issue 4 849  Fannie Mae Foundation 1998. All Rights Reserved. The Spatial Mismatch Hypothesis: A Review of Recent Studies and Their Implications for Welfare Reform Keith R. Ihlanfeldt and David L. Sjoquist Georgia State University Abstract In 1992, Housing Policy Debate published John Kain’s comprehensive review of the extensive scholarly literature on the spatial mismatch hypothesis. This hypothesis maintains that the suburbanization of jobs and involuntary housing market segre- gation have acted together to create a surplus of workers relative to the number of available jobs in submetropolitan areas where blacks are concentrated. Since Kain’s review, more than two dozen new studies on the spatial mismatch hy- pothesis have been completed. Generally, these studies use more suitable data and superior methodologies than earlier studies and therefore provide the most reliable evidence to date on the spatial mismatch hypothesis. This article critically reviews the new studies and assesses what implications can be drawn for welfare reform. Keywords: Labor market; Discrimination; Welfare Introduction The last half of the 1980s witnessed a revival of interest in the idea that the suburbanization of jobs and serious limitations on black residential choice have acted together to create a surplus of workers relative to the number of available jobs in inner-city neighborhoods where blacks are concentrated. This situation may result in jobless- ness, lower wages, and longer commutes for black workers. This idea was first expressed by John Kain (1968) and subsequently has been labeled the spatial mismatch hypothesis (SMH). If valid, the SMH has an important implication for current welfare reform; namely, that the success of welfare-to-work programs may hinge upon improving welfare recipients’ access to suburban jobs. Six different reviews of the SMH literature were published in the early 1990s (Holzer 1991; Ihlanfeldt 1992; Jencks and Mayer 1990; Kain 1992; Moss and Tilly 1991; Wheeler 1990). With the exception of Jencks and Mayer, these reviews concluded that the weight of the empirical findings provided either strong (Kain, Ihlanfeldt) or mod- erate (Wheeler, Moss and Tilly, Holzer) support for the hypothesis. Jencks and Mayer concluded that ‘‘the support [for the idea that job