This volume is an attempt to capture the essence of the state-of-the-art of intelligent agent technology and to identify the new challenges and opportunities that it is or will be facing. The most important feature of the volume is that it emphasizes a multi-faceted, holistic view of this emerging technology, from its computational foundations — in terms of models, methodologies, and tools for developing a variety of embodiments of agent-based systems — to its practical impact on tackling real-world problems.