- Agents and multi-agent systems (MAS) are a branch of Artificial Intelligence (AI) that attempts to combine AI, distributed system, and software engineering in a single discipline. For more than three decades, agents and MAS have been studied, implemented, and evaluated. Significant research and practice efforts were invested in moving agents from science to engineering and from labs to the field. To facilitate engineering, the agent-oriented software engineering community has produced methods, methodologies, and tools in support of agent and MAS development. The Foundation for Intelligent Physical Agents (FIPA) organization has delivered specifications and standards. Agent programming languages have flourished. These are all vehicles that aim to facilitate development and deployment of agents and MAS in practice.