Distributed A1 (DA1) is the branch of A1 concerned with how to coordinate behaviour among a collection semi-autonomous problem-solving agents - how they can coordinate their knowledge, goals and plans to act together, to solve joint problems, or to make individually or globally rational decisions in the face of uncertainty and multiple, conflicting perspectives. Distributed, coordinated systems of problem solvers are rapidly becoming practical partners in critical human problem-solving environments, and DAI is a rapidly developing field of both application and research, experiencing explosive growth around the world. This book presents a collection of articles surveying several major recent developments in DAI. The book focuses on issues that arise in building practical DAI systems in real-world settings, and covers work undertaken in a number of major research and development projects in the US and in europe. It provides a synthesis of recent thinking, both theoretical and applied, on major problems of DAI in the 1990s.