Ontology versioning deals with the management of ontology changes, including the evaluation of the consequences arising from these changes. We describe a distributed, “pluggable” blackboard architecture for managing different ontology versions. This allows existing environments for ontology design to be naturally extended with versioning capabilities with little or no overhead. We also outline how some core components of our architecture can be linked together, showing how this can be used to manage ontology versions, reasoning with and about them.