text: Appendix A
  Command and Support Relationships
  Echelons above brigade commanders and staffs must clearly understand both joint and
  Army command and support relationships. This appendix defines and describes joint
  command relationships and other authorities, followed by a discussion of Army
  command and support relationships. It concludes with a discussion of command and
  control considerations for multinational operations.
  CHAIN OF COMMAND
  A-1. The President and Secretary of Defense exercise authority and control of the Armed Forces through
  two distinct branches of the chain of command, as described in Chapter 1. One branch runs from the
  President, through the Secretary of Defense, to the combatant commanders for missions and forces assigned
  or attached to combatant commands. Within their commands, combatant commanders establish joint
  command relationships among forces as described in paragraphs A-3 through A-11.
  A-2. For purposes other than the operational direction of the combatant commanders, the chain of command
  runs from the President to the Secretary of Defense to the secretaries of the military departments and, as
  prescribed by the secretaries, to the commanders of military Service forces. The military departments,
  organized separately, operate under the authority, direction, and control of the secretary of that military
  department. The secretaries of the military departments exercise ADCON over Service forces through their
  respective Service chiefs and Service component commanders as described in paragraphs A-16 through A-17.
  JOINT COMMAND RELATIONSHIPS
  A-3. Command is central to all military action, and unity of command is central to unity of effort. The
  authority that a military commander lawfully exercises over subordinates, including the authority to assign
  missions and accountability for their successful completion, is inherent in command. Although commanders
  may delegate authority to accomplish missions, they may not absolve themselves of the responsibility for the
  accomplishment of these missions. Authority is never absolute; the extent of authority is specified by the
  establishing authority, directives, and law. The four types of joint command relationships are—
  * Combatant command (command authority) (COCOM).
  * OPCON.
  * TACON.
  * Support.
  A-4. The specific command relationship (COCOM, OPCON, TACON, or support) defines the authority a
  commander has over assigned or attached forces as each is summarized in this section. (See JP 1 for the full
  discussion of the authorities for each joint command relationship).
  COMBATANT COMMAND (COMMAND AUTHORITY)
  A-5. Combatant command (command authority) is the nontransferable command authority, which cannot
  be delegated, of a combatant commander to perform those functions of command over assigned forces
  involving organizing and employing commands and forces; assigning tasks; designating objectives; and
  giving authoritative direction over all aspects of military operations, joint training, and logistics necessary to
  accomplish the missions assigned to the command (JP 1). COCOM is the command authority over assigned
  forces vested only in commanders of combatant commands or as directed by the President or the Secretary
  of Defense and cannot be delegated or transferred. The combatant commander exercises COCOM of assigned