Mary Anderson Bain (September 19, 1911 – August 7, 2006) was a New Deal politician best known for her 33 years of service as Chief of Staff for Representative Sidney R. Yates, of Illinois.
In 1935 she became the director of the National Youth Administration, one of Franklin D. Roosevelt's New Deal agencies, for the Northern Illinois District.
Bain's career on Capitol Hill began in 1965, when she became Chief of Staff to Representative Sidney R. Yates (D-Ill.).
Yates became chairman of the House Appropriations Committee’s Subcommittee on Interior and Related Agencies in 1975.
Together Yates and Bain worked to promote the preservation of the nation's cultural heritage and history through the founding of the U.S.