This book reports on the 1990-91 World Values Survey as well as more detailed studies by the authors of value changes in Europe. The central hypothesis is that higher levels of economic development bring a shift from "materialist" to "postmaterialist" values--that is, less concern with economic and physical security and more with freedom, self-expression, and quality of life. The study clearly documents such a shift in Europe over the past generation but seeks to generalize these findings to 40 societies representing 70 percent of the world's population. This shift in values provides part of the answer to the strong empirical correlation between development and stable democracy first noted by Seymour Martin Lipset and confirmed more recently by Adam Przeworski. Past a certain level of income, the kind of participation and recognition provided by liberal democracies become more important to people than basic survival.