ATP 3-21.8 Introduction and Preface


ATP 3-21.8 is presented here for training purposes only. The Third Infantry Division Realism Gaming Unit ( has not been endorsed, authorized, or approved in any capacity by the United States Army, The Maneuver Center of Excellence, or the Department of Defense.


ATP 3-21.8 provides the doctrinal framework for all Infantry platoons and squads. It provides techniques for employment of Infantry platoons and squads in conducting decisive actions.

The principle audiences for ATP 3-21.8 are commanders, staffs, and leaders who are responsible for planning, preparing, executing, and assessing operations of the Infantry platoon and squad. It serves as an authoritative reference for personnel developing doctrine materiel and force structure, institutional and unit training, and standard operating procedures (SOPs) for Infantry platoon and squad operations.

Commanders, staffs, and subordinates ensure their decisions and actions comply with principles and expectations of the Army Profession and any applicable U.S., international, and, in some cases, host-nation laws and regulations. Commanders at all levels ensure their Soldiers operate in accordance with the law of war and ROE. (Refer to FM 27-10 for more information.)

ATP 3-21.8 uses joint terms where applicable. Selected joint and Army terms and definitions appear in both the glossary and text. Terms for which ATP 3-21.8 is the proponent publication (the authority) are italicized in the text and are marked with an asterisk (*) in the glossary. Terms and definitions for which ATP 3-21.8 is the proponent publication are boldfaced in the text. For other definitions shown in the text, the term is italicized and the number of the proponent publication follows the definition. These doctrinal principles and procedures are intended as guides and are not to be considered prescriptive. This publication outlines the framework in which the Infantry platoon and squad will operate separately or as part of a combined arms team.

ATP 3-21.8 applies to the active Army, the U.S. Army National Guard, Army National Guard of the U.S., and the U.S. Army Reserve unless otherwise stated. It is designed for platoon, squad and company level chains of command, company grade officers, senior and junior noncommissioned officers (NCOs), U.S. Army Training and Doctrine Command (TRADOC) institutions and components, and the U.S. Army Special Operations Command.

The proponent and preparing agency of ATP 3-21.8 is the United States Army Maneuver Center of Excellence (MCoE).


Army Techniques Publication (ATP) 3-21.8 encompasses techniques for the Infantry platoons and squads of the Infantry, Stryker, and Armored brigade combat teams (I, S, and ABCT s). It replaces Field Manual (FM) 3-21.8, published in March 2007, Army Tactics Techniques, and Procedures (ATTP) 3-21.71, published in November 2010, and ATTP 3‑21.9, published in December 2010. ATP 3-21.8 provides doctrinal guidance; describes relationships within the platoon and squad; defines organizational roles and functions, capabilities, limitations; and lay outs the responsibilities for platoons and squads during unified land operations. The Infantry platoon and squad is an all-weather, all-terrain unit. Against this backdrop, the Infantry platoon and squad must be ready to adapt to various levels of conflict and peace in various environments. This requires bold, aggressive, resourceful, and adaptive leaders– leaders of character, competence and commitment - who are willing to accept known risks to accomplish the mission. Infantry leaders must use their initiative and make rapid decisions to take advantage of unexpected opportunities.

This publication addresses the significant changes in Army doctrinal terminology, concepts, and constructs and proven tactics, techniques, and procedures (TTPs). The following paragraphs provide a summary by chapter:

Chapter 1 – Organization:

  • Provides a brief description of operational environments for Infantry platoons and squads. An overview of the Army's operational concept of unified land operations, operational structure, and law of war, rules of engagement (ROE), and combat power.
  • Addresses the role and organizational characteristics the Infantry platoon and squad as trained to conduct offensive, defensive, and stability tasks.
  • Addresses company team operations for the Stryker Infantry rife company, Infantry rifle company, and Armor and mechanized Infantry company.
  • Describes task organization, mission, capabilities, and limitations the Infantry platoon and squad echelons within all three brigade combat teams (BCTs) as well as the duties and responsibilities of personnel within those echelons.

Chapter 2 - Offense:

  • Addresses primary purpose of the offense—to decisively defeat, destroy, or neutralize the enemy force,or to seize key terrain.
  • Discusses offensive actions to deceive or divert the enemy, deprive them of resources or decisive terrain, collect information, or fix the enemy in position.
  • Describes offensive actions, during defensive missions, required to destroy an attacker and exploit success.
  • Addresses the following keys to offensive missions—identify the enemy’s decisive point; choose a form of maneuver avoiding the enemy’s strength while exploiting the enemy’s weakness; and ensure an operation massing overwhelming combat power.
  • Discusses basics and sequence of the offense, planning considerations, and direct and indirect fire planning, which apply to all offensive actions.
  • Concludes with synchronized attacks maximizing the Infantry’s unique capabilities and planning considerations in transitioning to other operations.

Chapter 3 - Defense:

  • Addresses primary purpose of the defense—to repel, to defeat, or to destroy an enemy attack and to gain the initiative for the offense.
  • Discusses the basics, characteristics, and planning considerations and direct and indirect fire planning of defensive missions the Infantry platoon and squad performs.
  • Describes the three defensive tasks—area defense, mobile defense, and retrograde operations.
  • Addresses five-step sequence of the defense during execution.
  • Discusses three basic forms of the defense: defense of a linear obstacle, perimeter defense, or a reverse-slope defense.
  • Addresses common defensive control measures.
  • Concludes with a discussion of planning considerations in transitioning to other operations.

Chapter 4 - Stability:

  • Discusses stability components of operations encompassing various military missions, tasks, and activities conducted outside the United States (U.S.) in coordination with other instruments of national power.
  • Addresses BCT support to stability tasks, essential offensive and defensive tasks, and planning considerations.
  • Describes conduct of mission command warfighting task— inform, influence and cyber/electromagnetic activities, replacement of the five Army information tasks (inform and influence, mission command warfare, information management, operations security ( OPSEC ), and military deception).
  • Terms information engagement, command and control warfare, and information protection are rescinded.
  • Provides discussion on transiting from operations focused on stability tasks to operations focused on offensive or defensive tasks.

Chapter 5 – Movement:

  • Describes the different types of movements, administrative and tactical.
  • Introduces the different types of movement formations and techniques.
  • Discusses route selection, navigational aids, and route types.
  • Provides techniques for crossing different types of danger areas and enemy contact at danger areas.
  • Addresses movement with combat vehicles mounted, unmounted and security aspects going along with mission, enemy, terrain and weather, troops and support available, time available and civil considerations (METT-TC).
  • Concludes with other movement situations, over water and under limited visibility.


Chapter 6─ Patrols and Patrolling:

  • Provides an overview of patrolling, organization of patrols, planning, coordinating patrols, patrol plan, departure from friendly lines and rally points.
  • Addresses combat patrols ambush, raid, and security, actions on objective, and combat patrol planning,
  • Discusses reconnaissance patrols area, route and zone, control measures and actions on reconnaissance objective.
  • Describes patrol preparations orders, briefings, rehearsals, and equipment.
  • Identifies post- patrol activities debriefs, equipment accountability and patrol reports


Chapter 7 - Sustainment:

  • Addresses the sustainment challenges to ensure continuous operations during combat.
  • Discusses sustainment the Infantry platoon and squad (its Soldiers) to ensure maneuver and conduct of combat operation.
  • Describes the process to continually anticipate Soldier needs and ensure the platoon and squad is properly sustained to conduct their mission.
  • Addresses anticipation of future sustainment needs critical to operations and to maintaining the momentum.
  • Focuses platoon and squad sustainment operations, includes unit responsibilities, company trains operations, and functions of sustainment.

Ten appendixes complement the body of this publication addressing procedures performed at platoon and squad level. They are as follows:

  • Appendix A describes the process of troop leading procedures (TLPs).
  • Appendix B describes direct fire planning and control.
  • Appendix C describes indirect fire support planning.
  • Appendix D addresses security.
  • Appendix E describes vehicle employment considerations.
  • Appendix F, addresses machine gun employment.
  • Appendix G describes and addresses shoulder-launched munitions (SLM) and close combat missile systems (CCMS).
  • Appendix H describes obstacle reduction and employment.
  • Appendix I covers chemical, biological, radiological, and nuclear (CBRN) operations.
  • Appendix J describes 14 selected battle drills for both the Bradley and Stryker.