While at t IBM and as a member of the OASIS DITA Technical Committee, he played a lead role in several DITA contributions including domain specialization, design constraints, data extensibility, map referencing, subject classification, and metadata schemes. His recent projects have used semantic search over structured content using both DB2 PureXML and Resource Description Framework (RDF) repositories. He has presented on DITA and on subject classification at Semantic Technologies, Extreme XML, OASIS Symposium, Content Management Strategies, and other conferences.