This book constitutes the refereed proceedings of the 11th International Conference on Applications of Natural Language to Information Systems, NLDB 2006, held in Klagenfurt, Austria in May/June 2006 as part of UNISCON 2006. The book presents 17 revised full papers and 5 revised short papers, organized in topical sections on concepts extraction and ontology, ontologies and task repository utilization, query processing, information retrieval and dialog processing, and NLP techniques.