The Senate's first office building, completed in 1908, served senators until 1958, when an additional structure was built. The most recent office building opened its doors in 1982. The buildings were named by resolution after prominent senators.
The Russell Senate Office Building, named for Senator Richard B. Russell, is the oldest of the Senate office buildings—as well as a significant example of the Beaux Arts style.
The Dirksen Senate Office Building is the second of the three office buildings. It is named after Senator Everett McKinley Dirksen.
Built as an extension to the Dirksen Building, this building is named after Senator Philip A. Hart.