Abstract. A crucial part of multi-agent system design is the design of agent interactions. Traditional approaches to designing agent interaction use interaction protocols, which focus on defining legal sequences of messages. Such approaches do not naturally exhibit flexibility and robustness, and are not a good match for intelligent software agents which are autonomous, proactive, flexible and robust. The Hermes approach to designing agent interaction uses interaction goals, actions, and a number of failure recovery mechanisms to give a design methodology which is a good fit with intelligent software agents. However, the Hermes approach only covers part of the design process. In this paper we integrate Hermes with the Prometheus methodology, thus providing a complete methodology for designing multi-agent systems where interaction design is goal-oriented, yielding flexible and robust interactions.