text: Chapter 16
  Passage of Lines
  This chapter discusses the performance of forward and rearward passages of lines. It
  first discusses general considerations, organization of forces, and control measures for
  a passage of lines. Next, the chapter discusses planning considerations associated with
  a passage of lines. Finally, it discusses a forward and rearward passage of lines.
  GENERAL CONSIDERATIONS FOR A PASSAGE OF LINES
  16-1. A passage of lines is an operation in which a force moves forward or rearward through another force’s
  combat positions with the intention of moving into or out of contact with the enemy (JP 3-18). There are two
  types: a forward passage of lines and a rearward passage of lines. Units perform a passage of lines to continue
  their attacks or perform counterattack, retrograde, and security operations that involve advancing or
  withdrawing through other units’ positions. A passage of lines potentially involves close combat. It involves
  transferring the responsibility for the assigned area between two units. That transfer of authority usually
  occurs when roughly two thirds of the passing force have moved through one or more passage points. The
  headquarters directing the passage of lines is responsible for determining when the passage of lines starts and
  ends. If not directed by higher authority, the stationary unit commander and the passing unit commanders
  determine—by mutual agreement—the time to pass command. They disseminate this information to the
  lowest levels of both organizations.
  16-2. Units have several reasons for conducting a passage of lines. These reasons include to—
  * Sustain offensive tempo.
  * Maintain the viability of the defense by transferring responsibility from one unit to another.
  * Transition from the performance of delay or security operation by one force to the defense.
  * Transition a unit for another mission or task.
  16-3. Units can conduct two variations of a passage of lines: a forward passage of lines or a rearward passage
  of lines. A forward passage of lines occurs when a unit passes through another unit’s positions while moving
  toward the enemy (ADP 3-90). A rearward passage of lines occurs when a unit passes through another unit’s
  positions while moving away from the enemy (ADP 3-90). Ideally, the passing unit’s operations do not
  interfere with the stationary unit.
  16-4. The headquarters directing the passage of lines is responsible for determining when the passage of
  lines starts and finishes. Because of the difficulty and risks inherent in a passage of lines, the headquarters
  directing the passage of lines usually positions C2 to oversee and deconflict the operation. The passing unit
  is responsible for establishing communications with the stationary unit. The only exception to this is when
  the passing unit is in direct contact, at which point to assist the unit in contact the stationary unit works to
  establish communications. Ideally, the headquarters responsible for the passage of lines co-locates the
  stationary force. If the headquarters responsible for the passage of lines is unable to co-locate with the
  stationary unit, then the passing unit establishes communications with the stationary unit.
  16-5. After receiving the warning order that directs a passage of lines, the passing unit’s commander and key
  staff representatives generally co-locate with the command post of the stationary unit to facilitate in planning
  the passage and establishing common situational understanding. If the passing unit cannot co-locate one of
  its command posts to help plan the passage, it conducts extensive liaison with the stationary unit.