Between 1980 and 2000, the population of metropolitan areas where less than 10 percent of adults had college degrees in 1980, grew on average by 13 percent. Among metropolitan areas where more than 25 percent of adults had college degrees, the average population growth rate was 45 percent. For more than a century, in both the United States and Great Britain, cities with more educated residents have grown faster than comparable cities with less human capital.1 There is no consensus, however, on the causes or implications of this relationship.