This book explores the exciting new field of Artificial Intelligence. It features in-depth coverage of important theoretical areas, including computational organization, computational economics, computational approaches in social science, and game theory. The concepton of the multi-agent system is particularly attractive, as it promises autonomy based on the conceptual speciality of a rational agent as well as collective behavior through interactions. The book draws out themes, especially the ideas of connectivity and natural computation, that reveal deep, underlying similarities between phenomena that have formerly been treated as completely distinct. The idea of agent-based approach is particularly rich in fresh approaches applicable to many fields such as artificial intelligence, computational organization, computational economics, and computational game theory.