On the Genealogy of Morality is one of Nietzsche's greatest works. Taking recent scholarship on board and using it to inform its analysis of this challenging text, Rex Welshon's Guide introduces readers of all levels to the major arguments found in the Genealogy. Welshon also shows how arguments Nietzsche develops elsewhere clarify and buttress what he says in the Genealogy. The guide begins by introducing the reader to Nietzsche's life, identifying some of his major intellectual influences, and tracking his influence on subsequent philosophers, artists, literary critics, social and political thinkers, and moral psychologists. Then, in four longer chapters, the Genealogy's Preface and three essays are investigated in detail. Each chapter is divided into two parts, the first dedicated to section-by-section examinations of Nietzsche's claims and arguments as they unfold in the book, the second to detailed analyses of the most important, intricate, and perplexing of those arguments. This structure permits readers to remain oriented through the Genealogy's unusual development and unique style. The guide then unpacks Nietzsche's arguments in greater detail, steering readers through arguments that sometimes lie behind the Genealogy's surface text and showing how recent scholarship has improved our understanding of some of its more cryptic claims. Throughout, the guide strives to remain accessible and avoid technical jargon and to keep Nietzsche's fascinating, if disturbing, insights into moral evaluation, moral history, and moral psychology front and center. Having read the guide, readers will be prepared to appreciate the Genealogy's many merits and identify some of its gaps.