With a large part of Europe's cultural heritage under threat, the European Community has agreed to sponsor a major project aimed at improving understanding of the factors that affect the stability of cellulose materials. The main aim of this project is to preserve the many millions of books, newspapers and printed documents in existence which are deteriorating because of air pollution, changes in the chemical composition of paper, and other effects. Assessment is also being made of the effectiveness of proprietary deacidification treatments intended to extend the useful life of cellulose-based materials. At the end of the project, scientists hope to be able to draw up recommendations as to how books and other reference works can be stored without risking decay. The three-year project, which was undertaken in the context of the Science and Technology for the Environment (STEP) programme, is coordinated by the Netherlands Institute for Applied Research (TNO) in cooperation with research institutes from Sweden and France.