What are the methodologies that we should employ for designing and evaluating governmental policy, in light of the profound effects that policies have on the level and distribution of individuals’ well-being? The Oxford Handbook of Well-Being and Public Policy is a comprehensive, interdisciplinary treatment of this question—drawing from welfare economics, moral philosophy, and psychology. Part I covers policy-assessment methodologies, both established and emerging. Part II reviews philosophical conceptions of well-being, and the literature on “subjective well-being” in psychology and economics. The chapters in Part III focus specifically on well-being measurement, proposing or empirically illustrating various approaches to constructing a comprehensive individual-level indicator of well-being—or, alternatively, defending a “multidimensional” approach that eschews such a measure. Part IV reviews a variety of challenges for policy assessment. This introductory chapter describes the Handbook structure and the role that each chapter plays therein and highlights a number of key Handbook themes.