Computability Theory presents a comprehensive, highly readable introduction to contemporary computability theory, techniques, and results. The author places the basic concepts and techniques in their historical, philosophical, and logical contexts, and offers an unusual breadth of coverage, including a number of advanced topics not usually addressed in books at this level. The result is an invaluable text, reference, and guide to the direction of current research in the field. The author brings the techniques and results of this beautiful and basic subject alive in an approachable and lively way.