THE NATIONAL LIBRARY OF MEDICINE, Located in Bethesda, MD; is the largest repository of medical literature in the world. Its vast holdings now comprise 2.3 million volumes and 3.6 million additional items, including manuscripts; photographs, prints, and other pictorial material; and extensive collections of microfilmed and audiovisual records. Today, this world-famous library faces a range of challenges related to the storage of the formidable volume of new material from around the world the preservation of older, documents, and the demand for technology-driven dissemination of information.