This book is a full-scale account of the morally important ideas of treating persons merely as means and treating them as ends. Audi clarifies these independently of Kant, but with implications for understanding him, and presents a theory of conduct that enhances their usefulness both in ethical theory and in practical ethics. There are many things to appreciate about this book. The chapters are rich with detailed examples which provide a valuable resource for teaching and for further study. Also, Audi has again demonstrated his mastery of the difficult feat of writing a serious philosophical text that has significant depth, while at the same time giving us a text that is jargon-free enough to be of use to the non-specialist. Furthermore, despite the theoretical focus of the book, practical concerns are never far from view. In fact, the final chapter focuses on the extent to which we have control over our treatment of one another and ends with a discussion that reveals his deep concern for acting morally toward one another. It's a lovely way to end a book about what it means to treat people as ends in themselves.