The design of intelligent trading agents, mechanisms, and systems has received growing atttention in the agents and multiagent systems communities in an e?ort to address the increasing costs of search, transaction, and coordination which follows from the increasing number of Internet-enabled distibuted el- tronic markets. Furthermore, new technologies and supporting business models areresultinginagrowingvolumeofopenandhorizontallyintegratedmarketsfor trading of an increasingly diverse set of goods and services. However, growth of technologies for such markets requires innovative solutions to...