text: Chapter 2
  2-125. The Army establishes organic command relationships through organizational documents such as
  tables of organization and equipment and tables of distribution and allowance. If temporarily task organized
  to another headquarters, organic units return to the control of their organic headquarters after completing the
  mission. To illustrate, within a maneuver brigade, the BSB and all other units within the brigade are organic
  to the headquarters. In contrast, within most support brigades, there is a base of organic battalions and
  companies (or sometimes just a headquarters) and a variable mix of assigned and attached battalions and
  companies.
  Assigned and Attached
  2-126. Commanders establish the assigned and attached command relationships by placing a subordinate unit
  under the command of another organization for a specified period of time. An assigned command relationship
  is relatively permanent. The gaining organization controls and administers the units or personnel for the
  primary function, or greater portion of the functions, of the unit or personnel. An attached command
  relationship is relatively temporary. The attachment may be for a specific mission or phase of an operation.
  The commander establishes these command relationships in an OPORD issued to the subordinate commander
  and specifies the duration of the relationship in the order. Unless specifically stated in the OPORD, these
  command relationships include ADCON authority and responsibility for the gaining command.
  OPCON and TACON
  2-127. Commanders establish the OPCON and TACON command relationships by placing a subordinate
  unit under the command of another organization for a specified period of time. OPCON is the authority to
  perform those functions of command over subordinate forces involving organizing and employing commands
  and forces, assigning tasks, designating objectives, and giving authoritative direction necessary to accomplish
  the mission. TACON is a command authority over units made available for tasking that is limited to the
  detailed direction and control of movements or maneuvers within the operational area necessary to
  accomplish missions or tasks assigned. The commander establishes these command relationships in an
  OPORD issued to the subordinate commander and specifies the duration of the relationship in the order.
  Unless specifically stated in the OPORD, these command relationships do not include ADCON authority and
  responsibility for the gaining command. Once the duration of the relationship has lapsed, the unit returns to
  its parent unit.
  Command Relationship Authorities and Responsibilities
  2-128. Inherent authorities and responsibilities associated with each command relationship are shown below.
  Commanders use these responsibilities to identify and establish the appropriate command relationship based
  on the mission requirements.
  2-129. Task organization authority:
  • Units with an organic command relationship may only be task organized by the organic
  headquarters.
  • Units with assigned, attached, or OPCON command relationships may be task organized by the
  gaining unit.
  • Units with a TACON command relationship may only be task organized by the parent unit.
  2-130. ADCON authority: Organic, assigned, and attached command relationships incur ADCON authority
  on the organic or gaining unit.
  2-131. Position/AO assignment: Units with an organic command relationship are assigned a position or AO
  by the organic headquarters. In all other command relationships, the gaining unit assigns positions/AO.
  2-132. Provide liaison: This is not applicable to units with organic command relationships. For all other
  command relationships, a liaison is provided as required by the gaining unit.
  2-133. Establish/maintain communications: This is not applicable to units with organic command
  relationships. For assigned and attached command relationships, communication is established and
  maintained as required by the gaining unit. For OPCON and TACON command relationships,
  communication is established and maintained as required by the parent and gaining unit.