This volume is a collective exploration of major themes in the work of Crispin Wright, one of today's leading philosophers. These newly commissioned papers are divided into four sections, preceded by a substantial Introduction, which places them in the context of the development of Wright's ideas. The distinguished contributors address issues such as the rule-following problem, knowledge of our meanings and minds, truth, realism, anti-realism and relativism, as well as the nature of perceptual justification, the cogency of arguments such as G. E. Moore's celebrated proof of an external world, and scepticism about the material world. Some papers explore the relationship of Wright's ideas with those of Ludwig Wittgenstein, whose influence has always been a prominent aspect of Wright's philosophy. The essays collectively testify to the enormous interest and relevance of Wright's seminal contributions for present-day debates in areas as diverse as the philosophy of language and mind, metaphysics, and epistemology, and significantly advance research in these areas. The volume also contains Wright's substantial responses to his critics, which offer the most up-to-date versions of his ideas and a vigorous defence of his philosophy.