PD Dr. Steffen Staab is a senior lecturer in applied computer science at the University of Karlsruhe. He has earned a M.S.E. from University of Pennsylvania, a Dr. rer. nat. from University of Freiburg and his habilitation from University of Karlsruhe. He has done research in the fields of computational linguistics, text mining, ontology engineering, knowledge management, and peer-to-peer. He has co-authored over 120 refereed publications and published 7 books, including a Handbook on Ontologies. In 1999, Steffen Staab has co-founded Ontoprise, the first Semantic Web company. He serves on the editorial board of IEEE Intelligent Systems, Journal of Web Semantics, Journal of Human-Computer Studies and Journal of Information Technology and Tourism. Steffen Staab has co-chaired a large number of workshops and several conferences. Recently, he serves as an area chair of ECAI-2004, Semantic Web track chair of WWW-2005, and co-chair of STAIRS-2004. Dr. Heiner Stuckenschmidt Heiner Stuckenschmidt holds a post-doc position in the Knowledge Representation and Reasoning Group at the Vrije Universiteit Amsterdam where he received his PhD for work on Ontology-Based Information Sharing on the Semantic Web. He works includes Semantic Web related topics such as ontology languages, knowledge-based meta data management and robust and scalable terminological reasoning. Before moving to Amsterdam, he was employed as a researcher and lecturer at the University of Bremen. His research activities in Bremen included the application of ontologies for information sharing in web based information systems with a special focus on semantics-preserving information integration and spatially related information. He is organizer of a series of workshops on ontologies at international conferences (IJCAI'01, ECAI'02, IJCAI'03) and member of program committees of several semantic web related conferences (SWWS'01, ISWC'02, WWW'03) and has held / will hold tutorial at different conferences (K-CAP 2001, IJCAI'03, ISWC'03). He is editor of a book on the application of ontologies in the cadastral domain the author of a book on Information Sharing on the Semantic web and has published more than 40 paper in international journals, conferences and workshops.