Speech is, in many respects, a socially constructed behavior, a fact which has important policy as well as scientific implications since a range of public policies affect the degree of racial and economic segregation found in all aspects of American life. Previous research in sociolinguistics has documented substantial variation in language patterns across social class lines, and across neighborhoods of different socio-economic and racial compositions as well. However it is important to note that this observed variation in language patterns across neighborhoods need not reflect the causal influences of neighborhood environments themselves. Many families have at least some degree of choice about where they live. Neighborhood attributes could be correlated with speech patterns simply because certain types of families wind up selecting to live (or being selected by housing agencies to live) in particular neighborhoods. This study offers a rare opportunity to understand the causal effects of neighborhood social environments on speech through the inclusion of speech and language measures as part of the large-scale data collection carried out for the U.S. Department of Housing and Urban Development's Moving to Opportunity (MTO) residential mobility experiment. Between 1994 and 1998, MTO enrolled a sample of low-income African-American and Latino families living in public housing and randomly assigned the chance to use a housing voucher to move to lower-poverty areas, while others received no additional mobility assistance. Speech measures were collected as part of the 10-15 year follow-up study of MTO adults and youth. In the current project, sociolinguist John R. Rickford of Stanford and economist Jens Ludwig of the University of Chicago will explore the linguistic correlates of HUD's large-scale social experiment. The findings could inform our understanding of the long-term effects of geographic dislocation on displaced populations.