Very Large Business Applications (VLBA) are defined as Enterprise-wide IS and beyond. They support the execution of business processes along the value chain and are not limited to the borderlines of a company. Examples of VLBA are ERP systems, corporate environmental management information systems, systems for computer integrated manufacturing and inter-organizational systems like CRM or SCM systems. From a technical perspective this systems are distributed, federated and integrated. The implementations are based on architectural concepts and sophisticated technologies like for example service oriented architectures (SOA), component frameworks, p2p-networks, grid-architectures and mediators.