This book constitutes the proceedings of the 5th International Conference on Web Information Systems Engineering, WISE 2004, held in Brisbane, Australia in November 2004.The 45 revised full papers and 29 revised short papers presented together with 3 invited contributions were carefully reviewed and selected from 198 submissions. The papers are organized in topical sections on Web information modeling; payment and security; information extraction; advanced applications; performance issues; linkage analysis and document clustering; Web caching and content analysis; XML query processing; Web search and personalization; workflow management and enterprise information systems; business processes; deep Web and dynamic content; Web information systems design; ontologies and applicatoins; multimedia, user interfaces, and languages; and peer-to-peer and grid systems.