Despite the continuing popularity of egalitarian values and rhetoric, the brute facts of poverty and massive inequality remain everywhere with us. Although extreme poverty and deprivation are often associated with developing societies, recent years have witnessed rising inequality in many industrialized countries as well. If inequality persists in modern societies, however, its patterns and structures are evolving in complex ways that defy generalizations from historical experience. This is nowhere more apparent than in the field of class analysis, where some commentators contend that class-based inequalities are weakening and that the concept of class is a sociological relic, while others attend to unprecedented increases in income inequality, the rise of an underclass, and the deepening spatial divide between rich and poor. The trajectory of modern race relations has proven equally complex, with some scholars celebrating the demise of overt prejudice while others emphasize the emergence of insidious forms of symbolic racism and the intensification of racial and ethnic conflicts worldwide. The subfield of gender stratification likewise reveals a tension between scholars who observe the rise of formally egalitarian attitudes and institutional practices and those who emphasize, instead, the persistence of discrimination, sex segregation, and wage inequality. Studying the changing structure of social inequality and its underlying causes and consequences, this text encourages diverse methodologies and approaches, including conceptual and theoretical treatises, qualitative and quantitative analyses, and comparative and case-study approaches.