This book constitutes the refereed proceedings of the 13th International Conference on Applications of Natural Language to Information Systems, NLDB 2008, held in London, UK, in June 2008. The 31 revised full papers and 14 revised poster papers presented together with 3 invited talks and 4 papers of the NLDB 2008 doctoral symposium were carefully reviewed and selected from 82 submissions. The papers are organized in topical sections on natural language processing and understanding, conceptual modelling and ontologies, information retrieval, querying and question answering, document processing and text mining, software (requirements) engineering and specification.