text: Fundamentals of Operations
  artillery, and armored formations outside the assigned area whose movement or employment may impact
  current and future operations. The area of interest also includes adjacent and other friendly forces whose
  actions or inactions of friendly forces could affect operations.
  3-139. Commanders consider all forms of contact possible with enemy forces and update their area of
  interest as the situation develops, including the effects of enemy influence and disinformation. An area of
  interest surrounds an assigned area, extending forward and to the flanks of the assigned area, and overlapping
  with adjacent unit assigned areas. Depending on the operation, it may also extend rearwards, especially when
  enemy forces contest operational and strategic lines of communications. A unit’s area of interest is especially
  important for helping leaders assess risks and maintain situational awareness of factors that will become
  important as operations progress. It is particularly important that the area of interest account for human,
  information, and physical dimension factors across all domains.
  DEEP, CLOSE, AND REAR OPERATIONS
  3-140. Within assigned areas, commanders organize their
  operations in terms of time, space, and purpose by Commanders balance combat power
  synchronizing deep, close, and rear operations. An echelon’s between requirements for deep, close,
  focus in time, space, and purpose—not necessarily their and rear operations while weighting the
  physical location—determines whether they are deep, close, main effort to accomplish the mission.
  or rear operations. This model assists commanders and staffs
  in synchronizing capabilities that reside outside of their unit’s assigned area, (for example, from air, space,
  and cyberspace) with operations inside their assigned areas. The degree of convergence that a corps can
  achieve to set conditions for its subordinate divisions depends on its ability to synchronize close, deep, and
  rear operations among its subordinate echelons and with the joint force.
  3-141. Divisions and higher echelons typically align their deep, close, and rear operations to corresponding
  areas, due to the scale of forces and physical considerations involved. This facilitates their C2 of forces spread
  over wide distances whose physical locations do not correspond to the location and purpose of their effects.
  Typically, divisions and corps assign command posts to enable control of these areas. For example, a division
  may position an artillery battery in a position area for artillery located in the rear area but employ its fires in
  support of close operations. In this case, the rear command post might control the battery’s sustainment and
  protection, but the division main command post will control its priorities for providing indirect fire support.
  At brigade echelons and below, differentiating between close, deep, and rear may have less utility during
  large-scale combat operations because of the high tempo, narrow focus, and short planning horizons. At every
  echelon, however, commanders must understand the relationship among these operations and their combined
  impact on mission accomplishment. (See FM 3-94 for more information about deep, close, and rear areas.)
  Figure 3-4 on page 3-28 illustrates notional corps deep, close, and rear areas for a corps AO with contiguous
  divisions.
  Note. The symmetry of figure 3-4 on page 3-28 provides the simplest way for understanding the
  operational framework which is a mental model. Applying the model to real situations results in
  significant variations.