This book constitutes the refereed proceedings of the 5th German Conference on Multiagent Systems Technologies, MATES 2007, held in Leipzig, Germany, September 2007, co-located with NetObjectDays, NODe 2007. The papers are organized in topical sections on engineering multi-agent systems, multi-agent planning and learning, multi-agent communication, interaction, and coordination, multi-agent resource allocation, multi-agent planning and simulation, as well as trust and reputation.