"Today, no economist studying the spatial economy of urban areas would ignore the effects of race on housing markets and labor market opportunities, but this was not always the case. Through what can be seen as a consistent and integrated research plan, John Kain developed many central ideas of urban economics but, more importantly, legitimized and encouraged scholarly consideration of the geography of racial opportunities. His provocative (and prescient) study of the linkage between housing segregation and the labor market opportunities of Blacks was a natural outgrowth of his prior work on employment decentralization and housing constraints on Black households. His more recent program of research on school outcomes employing detailed administrative data was an extension of the same empirical interest in how the economic opportunities of minority households vary with location. This paper identifies the influence of John Kain's ideas on different areas of research and suggests that his scientific work was thoroughly interrelated"--National Bureau of Economic Research web site.