A U.S. Congressional Chief of Staff is the top executive in the office of a member of the United States Congress. Chiefs of staff may also be called "Administrative Assistants," not to be confused with simple secretaries.

Very much like an office manager, they supervise all the aspects of a Congressional office including personnel decisions and policy initiatives. A chief of staff is usually the alpha in a congressional office responsible only to the Member; however, there are some offices that have less traditional hierarchies. They may also be assigned to such political undertakings as campaign finance fund raising and campaign organization. From time to time a CoS may be based out of a district office, but they are almost always found on the Hill. Usually they are very experienced working on Capitol Hill or are a personal friend of the Member. Some chiefs of staff got their positions by previously serving as a campaign manager. Salaries tend to be near or above $100,000.

Chiefs of Staff to Senators of the 109th Congress

Listed alphabetically by Senator's last name. The two Senators from Hawaii label their Chiefs of Staff as Administrative Assistants. This practice is usually more common in the House and Senators Akaka and Inouye are the only Senators who have Administrative Assistants.

List from the C-SPAN 2006 Congressional Directory--109th Congress, 2nd Session