In April of 2020, the Commanding General, Combined Arms Center, directed all Army Centers of Excellence to develop bottom-up doctrine. What is bottom-up doctrine you might ask? For Army Medicine, it is simply the tip of Asclepius’s staff, the Medical Platoon. With just a little over six months to execute, the U.S. Army Medical Center of Excellence Doctrine Literature Division put its collective heads together to tackle this daunting task. The commander’s intent was clear: provide platoon-level doctrine that can be handed to new platoon leaders and platoon sergeants as they graduate from the Basic Officer Leader Course and Noncommissioned Officer Senior Leader Course in order to better prepare them to lead their platoons upon arrival at their next duty station.Within the multi-domain battlefield, the sheer scale and scope of large-scale combat operations (LSCO) can cause volumes of casualties not seen since World War II. Operational medicine’s number one priority is supporting combat forces. Therefore, planning Army Health System (AHS) support, guided by the six AHS principles imbedded within the military decision-making process and troop leading procedures, becomes equally important to the actual treatment.The Army is currently transitioning from counterinsurgency operations to LSCO. After nearly two decades of conflict, operational medicine forces find themselves in the midst of redefining their culture with a generation of Soldiers unfamiliar with LSCO. To address this shift in culture, force modernization, training, leadership and education must focus AHS support to LSCO as opposed to support of limited contingency missions and operating in fixed facilities.Army Technique Publication 4-02.4, Medical Platoon, answers the call as it is one of the four cornerstone AHS publications designed to carry the reader through casualty response (self-aid/buddy aid), the medical platoon (Role 1), the medical company (Role 2), and theater hospitalization (Role 3). Army Techniques Publication 4-02.4 provides a platoon-level doctrinal approach that references pertinent Role 1 challenges of providing AHS support to the maneuver battalion.This publication delivers information on the structure and employment of medical platoons and sections that are organic to maneuver battalions and squadrons. It discusses the platoon’s ability to provide force health protection and health service support as a Role 1 medical capability within a brigade combat team’s area of operation. It is directed toward the medical platoon leader, medical platoon sergeant, and assigned providers as they conduct AHS support operations at the battalion level (Role 1). The tactics, techniques, and procedures provided in this publication are not all-inclusive but offer definitive information and provide doctrinal tools on training, planning, rehearsing, and conducting AHS support to the maneuver battalion. It describes the military decision-making processes and troop leading procedures required for AHS support operations and identifies interface and coordination requirements with other brigade medical elements.The material presented in this publication reflects enduring practices in providing timely AHS support to the tactical battalion commander. It depicts AHS operations from the point of injury or casualty collection point through the Role 1 battalion aid station (BAS). Each medical platoon or section possesses similar capabilities and functions but apply them in vastly different manners. To clearly delineate these types of units, and to detail the AHS support that a Role 1 provides to the various types of military operations, this publication contains five chapters and eight appendices:·       Chapter 1, The Role of the Medical Platoon or Section, provides a holistic view of the entire AHS within a brigade. It discusses the echelons above brigade medical forces that are in support of a brigade. This part of the publication describes the four types of brigades and their AHS support forces.·       Chapter 2, Command and Control, details the command and control requirements of the medical platoon leadership, including troop-leading procedures, the five-paragraph operations order, the military decision-making process, risk management, rehearsals, pre-combat checks and inspections, and after action reviews.·       Chapter 3, AHS Support to Operations, discusses how the medical platoon or section provides AHS support to operations and encompasses how it will support its maneuver battalion during offensive, defensive, and stability operations. It also details AHS support to operations conducted at night, in an urban environment, in the jungle, in the desert, and during mountainous and cold weather operations, wet gap crossings, subterranean operations, and airborne and air assault operations.·       Chapter 4, Sustainment, describes how the medical platoon or section performs sustainment operations, including medical logistics.·       Chapter 5, Chemical, Biological, Radiological, and Nuclear (CBRN) Operations, details how the medical platoon or section supports itself and the battalion in CBRN operations to include establishing the patient decontamination site.·       Appendix A, Analog Reports, details common reports a medical platoon or section is required to submit.·       Appendix B, Medical Battle Drills, discusses medical-specific battle drills required by medical platoons and sections to accomplish their mission effectively.·       Appendix C, Patient Evacuation, details casualty and medical evacuation platform litter and ambulatory capacities for the United States Army, Marine Corps, Navy, and Air Force.·       Appendix D, Force Health Protection and Medical Readiness, provides considerations for the medical platoon or section mission charged with maintaining the force health protection and medical readiness of the battalion.·       Appendix E, Medical Training Considerations, provides instructions on teaching combat lifesavers and field sanitation teams for the battalion. It also details required training for medical and nonmedical personnel within the battalion.·       Appendix F, Battalion-Level Symbology, lists common military symbols a medical platoon will encounter at the battalion level.·       Appendix G, Law of Land Warfare and Medical Ethics, discusses medical implications of the Geneva Hague Conventions and medical ethics.·       Appendix H, Tactical Standard Operating Procedures, provides detailed instruction on how to establish platoon-level tactical standard operating procedures.The dynamics and rapid shaping evolution of current combat operations will undoubtedly demand competent platoon-level leadership. Of equal if not greater importance is how we educate, organize, train, equip, and professionally develop medical platoon leaders and platoon sergeants. Doctrine is only one aspect guiding how we medically support the warfighter at the battalion level. However, doctrine is useless without the leaders and Soldiers trained and educated in its application, and a bottom-up approach to doctrine begins at the foundations with cornerstone publications. For this reason and in response to the directive of the Commanding General, Combined Arms Center, the Medical Center of Excellence Doctrine Literature Division has developed ATP 4-02.4, Medical Platoon, to outline doctrine, training, leadership and education considerations to help strengthen platoon leadership in providing battalion-level AHS support and their ability to prevail during LSCO on a multi-domain battlefield.