Saul Kripke is one of the most original and creative philosophers writing today. His work has had a tremendous impact on the direction that philosophy has taken in the last thirty years and continues to dominate some of its most fundamental aspects. Given Kripke's importance it is perhaps surprising that there is no introduction to his philosophy available to the general student. This book fills that gap. As much of Kripke's work is highly technical, the book's central aim is to provide clear exposition of Kripke's ideas in a form that is understandable to a beginning readership as well as a commentary on them that more advanced students will find useful. The book begins with a discussion of Kripke's early work on modal logic, which provides the foundation for many of his later philosophical contributions, before examining in detail Kripke's central ideas and arguments contained in Naming and Necessity. In further chapters, Kripke's work on semantic paradoxes and his theory of truth are outlined as well as his controversial interpretation of Wittgenstein's famous private language argument. Kripke's ideas are situated alongside those of his precursors and some of the most important and interesting responses to them are explored. The reader is thus able to appreciate the path-breaking nature of Kripke's contributions, how they have challenged fundamentally traditional interpretations, and how they have sparked some of the most important philosophical debates of recent years.