Chief of staff is an important adviser, aide, or coordinator for an office holder. The Chief of staff is often the highest-ranking staff member or senior aide. It is used in the Pentagon, the White House, and by members of Congress.
In the White House the position was first introduced by President Eisenhower who brought the organizing principal with him from the Pentagon using the heirachial structure in the branches of the military, and has been used by subsequent presidents ever since. Members of Congress and Committees have also adopted the organizing model for their own congressional staffs.
In the military at the summit of the Army, Navy, and Air Force chiefs, and Marine commandant, are the Joint Chiefs of Staff.
In the White House the position is appointed by the president and serves on his behalf, conducting day-to-day duties such as managing the president's schedule, hiring staff members, filling other key positions throughout the administration, limiting access to the president, and coordinating legislstive proposals and votes with congressional party leaders and committee chairmen for the president's legislative agenda.
The president's Chief of staff has a dual function overseeing two statutory entities, the Executive Office of the President (EOP), and the White House Office. The EOP has some members that require Senate approval, OMB Director, Trade Representative, and members of the Council of Economic Advisors for example, whereas positions in the White House Office are considered the president's personal staff.
- In many administration's for example, sometimes the National Security Advisor has outranked the Chief of staff, answering to the president alone. In others, the National Security Advisor must go through the Chief of staff to gain access to the president.
- There is no law mandating a president use this structure. Each president is free to organize his operation of the White House as he sees fit.