text: Chapter 9
  actions of sustainment units and staffs at each echelon of support. Understanding Army echelons and
  sustainment unit and staff roles and capabilities are essential to conducting sustainment operations. Knowing
  the roles, responsibilities, and authorities of sustainment units is essential to planning, preparing, executing,
  and assessing sustainment operations. A critical element within the headquarters at each echelon is the
  sustainment cell at echelons above brigade and the sustainment staff (brigade and below) that works in
  conjunction with the supporting sustainment headquarters to plan and synchronize support during decisive
  action. Figure 9-3 depicts a notional area of responsibility (AOR) command and control structure of
  sustainment forces.
  Figure 9-3. Notional area of responsibility command and control of sustainment forces
  Note. Theater ASCCs also support Army special operations forces when performing theater
  special operations missions. Support to other Services while executing assigned executive agent
  or lead Service responsibilities is commonly referred to as Army support to other Services. In both
  instances, the ASCC supports sustainment requirements through its designated theater sustainment
  command (TSC), expeditionary sustainment command (ESC), and MEDCOM (DS).
  Theater Sustainment Command
  9-167. The TSC is the Army’s command for the integration and synchronization of sustainment in the AOR.
  The MEDCOM (DS) is also assigned to the ASCC (see paragraph 9-177). It is the theater medical command
  that is responsible for command and control, integration, synchronization, and execution of AHS support
  within the AOR. The TSC connects strategic enablers to the tactical formations. The TSC commander also
  commands and task organizes attached ESCs, sustainment brigades, and additional sustainment units. The
  TSC executes the sustainment concept of support for planning and executing sustainment-related support to
  the AOR. TSCs execute sustainment operations through their assigned and attached units. The TSC integrates
  and synchronizes sustainment operations across the AOR from a home station command and control center
  or through a deployed CP. The TSC has four operational responsibilities to forces in theater: theater opening,
  theater distribution, sustainment, and theater closing. The task organized TSC is tailored to provide
  operational-level sustainment support within an assigned AOR. It integrates and synchronizes sustainment