The John Adams Building is the second oldest of the buildings of the Library of Congress of the United States. Built in the 1930s, it is named for John Adams, the second president, who signed the law creating the Library of Congress in 1800. The building is in the Capitol Hill district of Washington D.C. next to the library's main building in the Capitol Complex. The Adams building opened to the public on April 5, 1939, and before being named for the president in 1980, was simply called The Annex building. It is designed in a restrained but very detailed Art Deco style and faced in white Georgia marble. It is located on Second Street SE between Independence Avenue and East Capitol Street in Washington, DC.

The Library of Congress (LOC) is a research library in Washington, D.C., that serves as the library and research service of the U.S. Congress and the de facto national library of the United States. Founded in 1800, the library is the United States's oldest federal cultural institution. The library is housed in three elaborate buildings on Capitol Hill. It also maintains a conservation center in Culpeper, Virginia. The library's functions are overseen by the Librarian of Congress, and its buildings are maintained by the Architect of the Capitol. The Library of Congress is one of the largest libraries in the world. Its collections contain approximately 173 million items, and it has more than 3,000 employees. 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 470 languages".