Abstract
This paper describes an open and flexible infrastructure to support dynamic collaboration among companies through the entire lifecycle of the virtual enterprise. The proposed approach is an agent-enhanced architecture on which the conversation model is grafted. The collaboration among enterprises is modeled by a collaboration policy which is a machine-readable specification of a pattern of message exchange among agents participating in the collaboration. The proposed system is widely open and highly flexible since various types of software, including Web services, can collaborate through the conversation model.