Library of Congress

Admission to the various research facilities of the library is free, and no introduction or credentials are required for persons over high school age. A photo identification and current address are required for the library's reading rooms and collections, and additional requirements apply for entry into certain collections like those of the Manuscript Division, Rare Book, and Special Collections Division, and Motion Picture, Broadcasting, and Recorded Sound Division. Priority is given to inquiries pertaining to the library's holdings of special materials or to subjects in which its resources are unique. Demands for service to Congress and federal agencies have increased, and thus reference service to others through correspondence is limited.