In 1957, Librarian of Congress L. Quincy Mumford initiated studies for a third Library building. Congress appropriated planning funds for that structure, today's James Madison Memorial Building, in 1960, and construction was approved by an act of Congress on October 19, 1965 that authorized an appropriation of $75 million. Excavation and foundation work began in June 1971, and work on the superstructure was completed in 1976. The cornerstone, inscribed with the date 1974, was laid on March 8, 1974. Dedication ceremonies were held on April 24, 1980, and the building actually opened on May 28, 1980.