The title chief of staff identifies the leader of a complex organization, institution, or body of persons and it also may identify a principal staff officer (PSO), who is the coordinator of the supporting staff or a primary aide-de-camp to an important individual, such as a president or a senior military officer.
In general, a chief of staff provides a buffer between a chief executive and that executive's direct-reporting team. The chief of staff generally works behind the scenes to solve problems, mediate disputes, and deal with issues before they are brought to the chief executive. Often chiefs of staff act as a confidante and advisor to the chief executive, acting as a sounding board for ideas. Ultimately the actual duties depend on the actual position and the people involved.
The chief of staff in a hospital in the United States or Canada is the primary leader of all divisions and staff, including divisions that have chiefs as well, such as, leadership over chief of surgery, chief of obstetrics, chief of orthopedics, etc. as divisions that each are headed by a leader in that specialty. The chief of staff is inevitably a physician, as opposed to the chief administrator, who is often a non-medical professional.Chief of Staff to the President of BrazilChief of Staff to the Prime Minister (Canada)Chief of Staff (Philippines), a former position in the Cabinet of the Philippines, serving under the President of the PhilippinesDowning Street Chief of Staff (United Kingdom)White House Chief of Staff (United States)Chief of Staff to the Vice President of the United StatesRivers State Chief of Staff (Nigeria)Chief of staff (United States Congress), the most senior staff member in the office of a member of the United States CongressPrincipal Staff Officer to the Prime Minister (Pakistan)In general, the positions listed below are not "chiefs of staff" as defined at the top of this page; they are the heads of the various forces/commands and tend to have subordinates that fulfill the "chief of staff" roles.
Chief of the Defence StaffChief of the General StaffChief of the Army StaffChief of the Air StaffChief of the Naval StaffCategory:Vice chiefs of staffChief of General Staff of Azerbaijani Armed Forces - head of General Staff of Azerbaijani Armed ForcesChief of the Defence Staff (Canada)Chief of the Air Staff (Canada)Chief of the Defence Staff (French: Chef d'État-Major des Armées, CEMA)Chief of Staff of the French Air Force (French: Chef d'État-Major de l'Armée de l'Air, CEMAA)Chief of Staff of the French Army (French: Chef d'État-Major de l'Armée de Terre, CEMAT)Chief of Staff of the French Navy (French: Chef d'État-Major de la Marine, CEMM)Chief of Staff of the French Gendarmerie (French: Directeur-Général de la Gendarmerie, DGGN)Chief of Defence StaffChief of the Army StaffChief of the Navy StaffChief of the Air Force Staffchief of staff in government
In Ireland
Chief of Staff of the Irish Defence ForcesChief of the Defence StaffChief of the Army StaffChief of the Navy StaffChief of the Air Force StaffJoint Chiefs of Staff Committee, headed by the Chairman Joint Chiefs of Staff CommitteeChief of Army StaffChief of Air StaffChief of Naval StaffCommandant of Pakistan MarinesCommandant of Pakistan Coast GuardChief of Staff, Armed Forces of the Philippines - exercises command and control over all elements of the Armed Forces of the PhilippinesChief of the General Staff of the Armed Forces (Portuguese: Chefe do Estado-Maior-General das Forças Armadas, CEMGFA) - operational commander of the Portuguese Armed ForcesChief of Staff of the Navy (Portuguese: Chefe do Estado-Maior da Armada, CEMA) - commander of the Portuguese NavyChief of Staff of the Army (Portuguese: Chefe do Estado-Maior do Exército, CEME) - commander of the Portuguese ArmyChief of Staff of the Air Force (Portuguese: Chefe do Estado-Maior da Força Aérea, CEMFA) - commander of the Portuguese Air ForceChief of the Defence Staff (United Kingdom) - the professional head of the British Armed Forces.Chief of the Naval Staff, more commonly called the First Sea LordChief of the General Staff, formerly the Chief of the Imperial General StaffChief of the Air StaffThe Sovereign is the Commander-in-Chief. The CDS heads the Chiefs of Staff Committee and is assisted by the Vice-Chief of the Defence Staff. The Queen is the head of each branch of the British Armed Forces; members of the Royal Air Force and the Army take an oath of loyalty to the Sovereign.
Joint Chiefs of Staff, headed by the Chairman of the Joint Chiefs of Staff (CJCS)Chief of Staff of the United States ArmyAn Army General (O-10) serving as the senior ranking officer within the United States Army, but subordinate to any Army O-10 serving as CJCS or Vice CJCSChief of Staff of the United States Air ForceAn Air Force General (O-10) serving as the senior ranking officer within the United States Air Force, but subordinate to any USAF O-10 serving as CJCS or Vice CJCSIn Unified Combatant Commands, headed by a General (O-10) or Navy Admiral (O-10)A Major General (O-8) or Navy or Coast Guard Rear Admiral (O-8) overseeing the command's directoratesIn military commands headed by a Lieutenant General (O-9), Vice Admiral (O-9), Major General (O-8) or Rear Admiral (O-8), or Brigadier General (O-7) or Rear Admiral, lower half (O-7)A Colonel (O-6) or Navy or Coast Guard Captain (O-6) overseeing the entire General Officer's/Flag Officer's command staff; in some cases may also be referred to as an Executive AssistantIn some commands and organizations, two officers in pay grade O-6 may be assigned as Chief of Staff and Executive Assistant, respectivelyStabschef, commander of the Nazi Sturmabteilung 