Anil Nerode, Director of the Mathematics Institute at Cornell, USA, is one of the most influential logicians in the world. This volume, published in his honour, contains much new and significant work. The papers in this book are principally concerned with mathematical logic and some of its applications in computing. The book contains papers on recursion theory, intuitionism, computability in group theory, recursive model theory, reverse mathematics and the extraction of programs from proofs. A survey of Nerode's technical achievements over the last 30 years is also included. In particular, the book features papers on new developments in the understanding of the properties of intuitionistic set theory and intuitionistic analysis, the extension of computability in ordinary mathematics pioneered by Marian Boykan Pour-El and Ian Richards, the proof-theoretic strength of a long-standing conjecture of Fraisse and an extension of, and further account of, the Curry-Howard method of extracting programs from logical proofs. The papers in general arose from the conference, "Logical Methods in Mathematics and Computer Science. A Symposium in Honor of Anil Nerode on the Occasion of his Sixtieth Birthday", held at the Mathematical Sciences Institute at Cornell University, from June 1-3, 1992.