Corporate knowledge consists both of information that is available throughout a company and of information technology frameworks and paradigms. Considering an enterprise as a distributed computational paradigm, multi-agent systems can be proposed to address knowledge management issues within a company. We consider in this paper a new approach for corporate knowledge based on the agent oriented ion paradigm. This paradigm provides a high level of abstraction. We investigate here the concept of virtual knowledge communities, which is a convenient concept for addressing dynamical distributed knowledge management. It allows improved simulation and support for knowledge management processes, and therefore to innovate with new methods in this field. Our approach is well-suited for instance to filter the amount of knowledge that is transmitted throughout a company. Key Words: Agent societies, Corporate knowledge, Agent oriented abstraction, Virtual knowledge communities