The Uniterm system of coordinate indexing, developed by the Armed Services Technical Information Agency, provides a method for the organization, storage, and retrieval of information. The contents of reports are analyzed, and terms are assigned to the documents. For each term there is a card upon which the accession number of documents assigned that term are entered. Reports may be retrieved by looking up the appropriate term or by comparing the document numbers on two or more term cards. Thus, the identical numbers appearing on the three cards "air" and "ducts" and "icing" would lead to documents on air duct icing. The document may then be retrieved directly, or a card containing bibliographic information, abstract, and uniterms may be consulted. Rules and directions for indexing and posting are given, along with some references and search methods. (LS)