This United States Army field manual, Army Techniques Publication ATP 3-09.12 Field Artillery Counterfire and Weapons Locating Radar Operations October 2021, contains the fundamental techniques and guidance required for planning, coordinating, conducting FA counterfire, and the employment of FA WLRs. It provides information on how to train and conduct operations and describes the techniques currently being used and known to be effective. The doctrine is consistent with joint, multi-Service, and other Army doctrine. Counterfire is an operations function that aims to accurately engage enemy indirect fire systems once acquired. The counterfire process is not the sole responsibility of the Fires Warfighting function and should be integrated with the planning process through targeting. FA target acquisition (TA) identifies and provides an accurate target location to the supported maneuver commander to allow for immediate counterfire operations against the target. This publication describes current and emerging fires TA systems. The main piece of equipment used for counterfire operations and TA is the WLR. ATP 3-09.12 explains the techniques for counterfire operations, employing and managing WLRs, and target processing. This publication describes TA techniques to accomplish the mission as stated in the operations order and to employ, maintain, and operate WLRs to locate the enemy indirect weapon systems. ATP 3-09.12 is divided into four chapters and eleven appendices: Chapter 1 Introduction to Field Artillery Counterfire and Targeting. Chapter 2 Roles and Responsibilities. Chapter 3 Field Artillery Counterfire/Weapons Locating Radar Sections and Personnel. Chapter 4 Employment Considerations for Weapons Locating Radars. Appendix A Automated Target Data Processing. Appendix B Friendly Fire Log. Appendix C Embedded Training. Appendix D Mask Considerations. Appendix E Support Requirements. Appendix F Tools and Procedures. Appendix G Rocket Artillery Mortar (RAM) Warn. Appendix H AN/TPQ-53 Weapons Locating Radar System Characteristics. Appendix I AN/TPQ-50 Weapons Locating Radar System Characteristics. Appendix J AN/TPQ-36 Weapons Locating Radar System Characteristics. Appendix K Target Acquisition Tab.