1. general staff, high command, headquarters (group of officers in charge of an army under the control of the commander-in-chief) (military)

2. headquarters (military installation from which troops are commanded and orders are issued) (military)

3. administrative staff (body of staff that administers a political party) (politics)

4. senior management (group of people in charge of a corporation) (business)

5. any administrative body aimed at aiding a professional or academic in their work (informal, by extension)