This volume constitutes the thoroughly refereed post-workshop proceedings of the 4th Australian Workshop on distributed Artificial Intelligence held in Brisbane, QLD, Australia in July 1998. The 13 revised full selected and invited papers presented were carefully reviewed and selected for inclusion in the book. The book is devoted to theoretical aspects, languages, and applications of various types of multi-agent systems. Among the topics covered are self-interested mobile agents, formal specification of MAS, coordination, reinforcement learning, self organization, agent negotiation, agent-based intelligent systems, Internet-based DAI applications, agent-based scheduling, Internet agent trading.