For over thirty years, Robert Audi has produced important work in ethics, epistemology, and the theory of action. This volume features thirteen new critical essays on Audi by a distinguished group of authors: Fred Adams, William Alston, Laurence BonJour, Roger Crisp, Elizabeth Fricker, Bernard Gert, Thomas Hurka, Hugh McCann, Al Mele, Walter Sinnott-Armstrong, Raimo Tuomela, Candace Vogler, and Timothy Williamson. Audis introductory essay provides a thematic overview interconnecting his views in ethics, epistemology, and philosophy of action. The volume concludes with his comprehensive response essay that yields an illuminating dialog with all his critics and often extends his previous work.