Soar is a state-of-the art computational theory of the mind that has had a significant impact in both artificial intelligence and cognitive science. Begun by John E. Laird, Allen Newell, and Paul S. Rosenbloom at Carnegie Mellon in the early 1980s, the Soar Project is an investigation into the architecture underlying intelligent behavior with the goal of developing and applying a unified theory of natural and artificial intelligence. The Soar Papers - sixty-three articles in all - provide in one place the important ideas that have emerged from this project. The book is organized chronologically, with an introduction that provides multiple organizations according to major topics. Readers interested in the entire effort can read the articles in publication order, while readers interested only in a specific topic can go directly to a logical sequence of papers to read on that topic. Paul S. Rosenbloom is Associate Professor of Computer Science at the Information Sciences Institute. John E. Laird is Associate Professor of Electrical Engineering and Computer Science at the University of Michigan. The late Allen Newell was U.A. and Helen Whitaker University Professor of Computer Science at Carnegie Mellon University. Major topics include: The direct precursors of Soar, the Soar architecture, implementation issues, intelligent capabilities (such as problem solving and planning, learning, and external interaction), domains of application, psychological modeling, perspectives on Soar, and using Soar.