This book constitutes the refereed proceedings of the 9th International Conference on Applications of Natural Language to Information Systems, NLDB 2004, held in Salford, UK in June 2004. The 29 revised full papers and 13 revised short papers presented were carefully reviewed and selected from 65 submissions. The papers are organized in topical sections on natural language, conversational systems, intelligent querying, linguistic aspects of modeling, information retrieval, natural language text understanding, knowledge bases, knowledge management and content management.