Combat Service Support

The term Combat Service Support (or CSS) is utilized by numerous military organizations throughout the world to describe entities that provide direct and indirect sustainment services to the groups that engage (or are potentially to be engaged) in combat.

For example, Defense Secretary Philip Hammond has described the United Kingdom's armed forces as having "teeth", units that are trained and equipped for actual fighting, that cannot function without an able, innovative "tail", units providing assistance such as logistical and transport capabilities. Specific groups involved in the U.K. armed forces include the Royal Signals and Royal Engineers agencies as well as the Royal Army Medical Corps and Royal Logistic Corps.

Many groups exist under the umbrella of the United States Department of Defense providing support activities.

The distinction between a sub-group of a larger organization providing 'combat service support' versus 'combat support' is often a blurred one, but the general rule is often that 'combat support' refers specifically to efforts focused around fighting itself (such as how the Military Intelligence Corps of the U.S. Army aims to collect combat-ready information).

Within the Australian Army, combat service support is provided to combat elements at various levels: first line (organic to battalion or regimental level), second line (at brigade level), and third line (at formation or higher). Thus, for example an infantry unit such as the 5th Battalion, Royal Australian Regiment will include a logistics company which fills supply, transportation and maintenance functions, while a combat brigade, such as the 7th Brigade, will be supported by a combat service support battalion such as the 7th Combat Service Support Battalion. At formation level, a CSS brigade – the 17th Combat Service Support Brigade – will provide health, signals, catering, transport, policing and other service support requirements.

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