Peer-to-peer (P2P) computing is currently attracting enormous public attention, spurred by the popularity of file-sharing systems such as Napster, Gnutella, and Morpheus. In P2P systems a very large number of autonomous computing nodes, the peers, rely on each other for services. P2P networks are emerging as a new distributed computing paradigm because of their potential to harness the computing power of the hosts composing the network, and because they make their underutilized resources available to each other.

Three especially commissioned invited articles appear in this volume: an introduction, and revised versions of the papers presented at the 1st International Workshop on Agents and Peer-to-Peer Computing, AP2PC 2002, held in Bologna, Italy in July 2002. The book is organized into topical sections on peer-to-peer services, discovery and delivery of trustworthy services, and search and cooperation in peer-to-peer agent systems.