Forget the alarming mass-media images of a crime-ridden, poverty-stricken Mexico. In this highly readable monograph, two of Mexico’s leading public intellectuals identify the country’s expanding, prosperous middle class -- similar in many ways to its counterparts in other emerging-market economies or, for that matter, in the United States -- as the dominant factor in a paradigm shift that is transforming modern Mexico for the better. Behind this fortuitous trend are steady, if modest, economic growth rates, more open and competitive markets, and the smaller families that result from sharply declining fertility rates. De la Calle and Rubio employ an admittedly elastic culture-based definition of “middle class”: families that believe that a better future is possible and see education as the best means to upward social mobility. Such a classification based on individuals’ aspirations will sit more comfortably with marketing firms and pollsters than with social scientists, who favor traditional metrics of income and wealth. But savvy companies and politicians who appeal to this burgeoning middle class will crush competitors still adhering to outdated mythologies.