Establishing the foundation of Collaborative Networks The need for computer-assisted collaboration, which originally manifested decades ago in manufacturing to establish small business-oriented networks of organizations in forms of supply chains or extended enterprises, is by now extended into a large number of other areas. While today production and service provision constitute the main areas of application for Collaborative Networks (CNs) worldwide, during the last decade virtual scientific laboratories, inter-enterprise collaborative engineering, crisis management, virtual institutes and virtual learning communities among others, are also rising within the wide spectnlm of application areas in need of CNs. These developments emphasize the urgency for establishing a sounder foundation for collaborative networks, namely in terms o/, theoretical principles and formal models, capturing the concepts, entities, behaviors, and operations of the CNs, and developing technology-independent infrastructure architecture, tools and methodologies. Further to the shorter-term, goal-oriented. and opportunity-based virtual organi­ zations, nowadays a variety of long term "strategic" association / coalition of organizations have emerged. These associations, earlier called clusters or clubs, act as the breeding environments for virtual organizations, and provide the necessary conditions and mechanisms to prepare their members towards dynamic and fluid establishment of potential opportunity-based virtual organizations. A good collection of active va Breeding Environments (VBEs) and Professional Virtual Communities (PVCs) can be found in various regions of the world.