Claudia Goldin and Lawrence F. Katz have been publishing scholarly “cliometric” articles on trends in American economic inequality and education for two decades. After they discovered that their research fit together if they addressed the historical relationships between education, technological change, and equality, they decided to merge efforts and publish somewhat integrated versions of their work in this volume. One of their goals was to examine those relationships over a time span greater than that used by other explorations of the pressing issue of increasing inequality in the United States since the 1990s. The authors begin in 1890 and emphasize the years from 1915 to the present.