text: Division Roles, Functions, and Organizations
  5-36. A mobile command group allows a division commander to move to the point of decision. Division
  commanders move about the AO to interact with their subordinate commanders and different staffs, assess
  the operation, make decisions, and issue guidance. What division commanders learn and see helps them
  mentally visualize adjustments needed in current and future operations. The mobile command group allows
  the commander to command from anywhere in the division AO. A mobile command group requires a security
  force. Usually, the unit tasked to secure the headquarters and headquarters’ battalion secures the mobile
  command group.
  5-37. A division commander selects the individuals who staff the mobile command group. These personnel
  are normally functional representatives of those staff sections which control combat operations (such as
  maneuver, fires, and intelligence) in addition to the air liaison officer, and when needed, a joint terminal
  attack controller. The mission and staff available, however, dictate its makeup.
  DIVISION EARLY-ENTRY COMMAND POST
  5-38. The early-entry command post is an ad hoc organization comprised of equipment and personnel from
  the staff of the tactical, main, and rear command posts. The tactical command post usually provides the base
  for the early-entry command post. The division adds or subtracts personnel based on mission requirements.
  The early-entry command post includes a mix of current operations personnel, planners, and sustainers able
  to coordinate the reception of the division and plan its initial operations. For joint forcible entry operations,
  the assault command post is the early-entry command post.
  SUBORDINATE FORMATIONS
  5-39. The capabilities of a division are tailored for each mission by adjusting the division’s composition.
  Usually, a division commands between two and five BCTs, a mix of functional and multifunctional brigades,
  and a variety of smaller enabler units. The smaller enablers usually come from higher echelon assets and
  augment the division’s capabilities. See figure 5-1 on page 5-10 for an example tailored division.