This book advances understanding of the manifestations, causes, and consequences of generosity. Synthesizing the findings of the 14 research projects conducted by the Science of Generosity Initiative and offering an appendix of methods for studying generosity, this comprehensive account integrates insights from disparate disciplines to facilitate a broader understanding of giving—ultimately creating a compendium of not only the latest research in the field of altruistic behaviors, but also a research roadmap for the future. As the author sequentially explores the manifestations, causes, and consequences of generosity, Patricia Snell Herzog here also offers analyses ranging from the micro- to macro-level to paint a full picture of the individual, interpersonal and familial, and collective (inter)actions involved in altruism and generosity. The author concludes with a call to stimulate further interdisciplinary generosity studies, describing the implications for emerging scholars and practitioners across sociology, economics, political science, religious studies, and beyond.