A headquarters unit is a specialised military unit formed around the headquarters of a commanding officer and the requirements of that position. As such, a headquarters unit is always a component of a larger unit.

Examples include:

• headquarters regiment, which usually controls a brigade, division or larger unit;^[1]
• headquarters battalion (controlling a regiment, brigade or larger unit);^[2]
• headquarters company (military unit) (controlling a battalion);^[3]
• headquarters platoon (controlling a company) ^[4]

Specific examples include:

• Headquarters and Headquarters Company (US Army)
• Headquarters and Service Company (US Marine Corps)