Discrimination's dynamic nature means that no single theory, method, data or study should be relied upon to assess its magnitude, causes, or remedies. Despite some gains in our understanding, these remain active areas of debate among researchers, practitioners and policymakers. The specially commissioned papers in this volume, all by distinguished contributors, present the full range of issues related to this complex and challenging problem. Part 1 explores innovations in methods and data collection that help to provide richer descriptions of inequality. Part 2 reviews empirical evidence on discrimination that people with disabilities, older workers and gay, lesbian and bisexual individuals face. Although discrimination among these groups is not new, this Handbook shows that economists are beginning to more fully document their experiences. Part 3 presents a balanced discussion of anti-discrimination policies and the impact of affirmative action. The methods and data chapters are particularly designed to encourage researchers to utilize the new approaches and develop new data sources.Accessible and comprehensive, the Handbook is the seminal reference on the economics of discrimination for academic and professional economists, graduate students, advanced undergraduates, practitioners, policymakers, and funders of social science research.