The reports presented in this publication reflect 18 months of work of the Preservation and Access Committee (Council of Library Resources, USA). All paper, and therefore every book, deteriorates with time. The rate of decay is very much greater with acid paper, that is, the majority of books printed after 1850. In US libraries some 25% of the books are classified as brittle, with the paper breaking after one or two double fold of a page corner. In addition, up to 80% of the books in these collections are acidic, and therefore without preventive action will eventually become brittle. The US Council on Library Resources established a committee on preservation and access to consider possible ways of dealing with the problem. While preservation is important, access is more important and increased access justifies the expense and effort involved. The report discusses the problem in general, emphasizing the need for preservation to employ the most up-to-date techniques available at the time, to ensure an efficient bibliographic system to avoid duplication of efforts and to encourage the establishment of preservation priorities and collaboration. -- ICCROM