Research in Information Systems has switched its focus from data to communication. The communication between different autonomous Information and Communication Systems requires a certain amount of intelligence of each system. The system should be able to know which queries it can/may handle and also be able to negotiate about the information that it will give. In short, these systems evolve into what is called Cooperative Information Agents. We show that basing the information contents of these agents on linguistic concepts and furthermore modelling the communications between the agents using speech act theory provides for a natural and sound setting for these CIAs as well as for Business Modelling. In addition, we describe a lexicon in which the conceptual meaning of the terms of communication can be defined. Together, these models provide an integrated semantics for CIAs. These can be interorganizational, as in EDI applications, or intraorganizational, as in Workflow Management.