Abstract
Ontologies play an important role in defining the terminology that agents use in the exchange of knowledge-level messages. As object-oriented modelling, and the Unified Modeling Language (UML) in particular, have built up a huge following in the field of software engineering and are widely supported by robust commercial tools, the use of UML for ontology representation in agent systems would help to hasten the uptake of agent-based systems concepts into industry. This paper examines the potential for UML to be used for ontology modelling, compares it to traditional description logic formalisms and discusses some further possibilities for applying UML-based technologies to agent communication systems.