Simon Harper  School of Computer Science, University of Manchester, Manchester, M13 9PL, UK (sharper@cs.man.ac.uk). Dr. Harper is a Research Fellow in the Information Management Group of the Department of Computer Science at the University of Manchester where he is working on integrated hypermedia and database solutions in accessibility. He comes from an industrial background as a software consultant with a major energy provider. His research interests are a synthesis of hypermedia, cognition, and rehabilitation engineering. He also works on the Journal of Web Semantics and is a Web developer for the ACM SigWeb.

Sean Bechhofer  School of Computer Science, University of Manchester, Manchester, M13 9PL, UK (seanb@cs.man.ac.uk). Mr. Bechhofer is a Lecturer in the Information Management Group of the School of Computer Science at the University of Manchester. Over the last 10 years, he has worked on tools and infrastructure to support the use of Semantic Web technology, publishing numerous articles in journals, conferences, and books. He was a key participant in the COHSE (Conceptual Open Hypermedia Service) project, which combined open hypermedia with ontological services to produce an early example of a Semantic Web application. He was also mainly responsible for developing OilEd, one of the first ontology development tools to use reasoning. He was a member of the W3C WebOnt Ontology Language Working Group, providing key experience that led to the acceptance of OWL as a W3C recommendation and implementing one of the first validating parsers for OWL, along with supporting infrastructure for the use of OWL in applications.