As wide a range as possible of materials to research enquiries by Congress
The Library's primary mission is to research inquiries made by members of Congress, carried out through the Congressional Research Service. It claims Its "collections are universal, not limited by subject, format, or national boundary, and include research materials from all parts of the world and in more than 450 languages." The Library has the right of transference of all USA copyrighted works and houses two copies of books, maps, illustrations, and diagrams printed in the United States.
