SB meaning in Governmental ?

As part of the early 21st century transformation of the United States Army from a division-based structure to a brigade-based army; the division support commands, corps support groups, and area support groups were inactivated and transformed to sustainment brigades (previously called sustainment units of action (SUS or SUA).

The sustainment brigade is designed to provide mission command for combat support and combat service support units. It can be adjusted in size to support anywhere from one to ten brigade combat teams (BCTs). A sustainment brigade has a joint capability that allows the Army to better manage the flow of logistics into the area of operations (AO) and provides support to other services for common logistics like fuel, common ammo, medical supplies, repair parts of wheeled vehicles, and so forth. A sustainment brigade is designed to operate independently in a theater of operations, in conjunction with other sustainment brigades under the command of a sustainment command (expeditionary),(ESC) or directly under a theater sustainment command.(TSC) When in theater, a sustainment command (expeditionary) will report to the theater sustainment command.

The sustainment brigade, attached to an ESC/TSC, provides mission command for all subordinate units, and provides sustainment in an area of operations as defined by the ESC/TSC. All sustainment brigades have the same general capability to manage theater opening, theater distribution, and sustainment operations. Each sustainment brigade is a multifunctional organization, tailored and task organized to provide support for multiple brigade-sized or smaller units. In the sustainment role, the brigade is primarily concerned with the continuous management and distribution of stocks, human resources support, execution of financial management support, and allocation of maintenance in the AO to provide operational reach to maneuver commanders. The sustainment brigade may require augmentation in those areas where it lacks staff expertise and/or functional support capabilities.

As of the last published information, there will be 31 sustainment brigades; 10 active duty brigades as part of the Army's active divisions, 2 independent active duty brigades, 10 Army National Guard brigades and 9 US Army Reserve brigades.