From Speech Acts to his most recent studies of consciousness, freedom and rationality, John Searle has been a highly influential figure among contemporary philosophers. This systematic introduction to the entire range of Searle's work begins with the theory of speech acts and proceeds with expositions of his writings on intentionality, consciousness and perception, including, as well, a careful presentation of the so-called Chinese Room argument. Barry Smith is a Julian Park Professor of Philosophy, University at Buffalo and Director of the Institute for Formal Ontology and Medical Information Science in the University of Leipzig. He is the author of Austrian Philosophy (Open Court, 1994) and of some 300 articles on ontology and other branches of philosophy. In 2001 he received the Wolfgang Paul Award of the Alexander on Humboldt Foundation. He is also the editor of The Monist: An International Journal of General Philosophical Inquiry.