This book is an exploration of what it takes for an event to count as an action. I first became interested in this topic nearly a decade ago while working on a different topic. I kept coming across philosophers making claims about the nature of action that seemed false or at least dubious to me. As a consequence I turned to the philosophy of action directly, to get to the heart of the matter. I have wrestled with this territory ever since. I hope that, with this book, I have finally earned the intuitions that put me at odds with the philosophers I was originally reading. This book develops...