This special issue consists of four revised and extended papers selected from the 19th International conference on Applications of Natural Language to Information Systems (NLDB 2014), which was organized in June 2014 in Montpellier, France. For nearly 20 years, NLDB conferences (http://nldb.org) bring together researchers interested in the use of natural language processing techniques in applications such as database querying, information systems architecture, software development, specification checking, and more recently, various applications dealing with automatic enrichment of and advanced search in large volumes of web content, including opinion mining and sentiment analysis. Authors of a selected number of contributions to the conference (13 full papers, 8 short papers, and 14 poster presentations, among the 73 submitted ones) were asked to develop their papers into journal articles. After additional reviewing, 4 papers were eventually selected for this special issue. The addressed topics (e.g, information retrieval, information extraction, reasoning, disambiguation) underline the various and complex issues addressed by the Natural Language Processing (NLP) and Information Systems (IS) communities.