Headquarters and Service Company

A Headquarters and Service Company is a company sized military unit, found at the battalion and regimental level in the U.S. Marine Corps. The U.S. Army equivalent unit is the Headquarters and Headquarters Company.

In identifying a specific headquarters unit, it is usually referred to by its abbreviation as H&S Company. While a line company is formed of three or four platoons, H&S is made up of the battalion headquarters, which includes the battalion or regimental command section and the battalion/regimental headquarters executive staff, and headquarters support personnel of a battalion, or regiment. As these personnel do not fall inside one of the line companies of the battalion or regiment, the H&S company is the unit to which they are administratively assigned. The typical personnel strength of an average H&S Company for a Marine infantry battalion is 269 personnel.

Inside a typical battalion H&S company, the battalion headquarters command section (CO, XO, and SgtMaj) and the battalion headquarters executive staff will usually include the following key personnel and primary staff officers:

Most of the executive staff sections (the "S" sections) contain at least one additional officer (S-1 & S-2) or up to several additional officers (S-3 has seven and S-4 has three) who serve as assistant staff officers or as functional managers within the staff section. An infantry battalion has one Navy Chaplain Corps officer (chaplain) and two Navy Medical Corps officers (surgeons), collectively referred to as the "special staff," as well as essential Navy and Marine Corps staff non-commissioned officers (SNCOs), chief petty officers (CPOs), non-commissioned officers, petty officers, and junior enlisted Marines and Navy hospital corpsmen who serve as support personnel in the occupational specialities of the executive staff sections (S1 through S4 and the S6) and special staff sections (chaplain and medical).

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