Network-based information systems use well-defined standards to ensure interoperability and also have a tightly coupled relationship between their internal data representation and the external network representation. Virtual organisations (VOs), where members share a problem-solving purpose rather than a location-based or formal organisation, constitute an environment where user requirements may not be met by these standards. A virtual organisation has no formal body to manage change requests for these standards so the user requirements cannot be met. We show how the decoupling of the internal and external representations, through the use of ontologies, can enhance the operation of these systems by enabling flexibility and extensibility. We illustrate this by demonstrating a system that implements and enhances the Domain Name System, a global network-based information system. Migrating an existing system to a decoupled, knowledge-driven system is neither simple nor effortless but can provide significant benefits.