Users wishing to consult the collection must make arrangements in advance. The renowned collection of trade catalogs, estimated at 285,600 pieces representing some 35,000 companies, is a national treasure documenting the history of manufacturing in this country. The collection consists of product catalogs, technical manuals, advertising brochures, price lists and company histories. Smithsonian researchers use them to provide primary documentation for objects in the Smithsonian collections, and the catalogs often provide the only precise identification of artifacts. They are useful for the information they give on prices, size and weight specifications, and some contain actual samples of paint chips, textiles, and plastics.
Processing continues for much of the collection.
The National Postal Museum Branch Library houses more than 3,000 books, approximately 5,000 journal titles, along with a collection of rare material and various stamp and auction catalogs. The branch collects material covering worldwide philatelic and postal history, primarily of the United States. There are some 10,000 photographs of philatelic and postal history subjects.