Field Manual (FM) 3-39 describes the operational doctrine of the Military Police Corps Regiment. The manual is linked to joint and Army doctrine to ensure that it is useful for joint and Army. Other military police FMs will be based on the foundations established in this manual and will be synchronized with their respective joint and Army publications. To comprehend the doctrine contained in this manual, readers must first understand the nature of unified land operations as described in Army Doctrine Publication (ADP) 3-0 and Army Doctrine Reference Publication (ADRP) 3-0. Readers of this manual must also fully understand the fundamentals of the operations process found in ADP 5-0 and ADRP 5-0, the principles of mission command as described in ADP 6-0 and ADRP 6-0, and the protection principles discussed in ADP 3-37 and ADRP 3-37. The principal audience for this manual is all commanders and staff elements at all echelons and military police personnel who are tasked with planning, directing, and executing military police missions. Training developers and educators throughout the Army will also use this manual. Commanders, staffs, and subordinates will ensure that their decisions and actions comply with applicable U.S., international, and (in some cases) host nation laws and regulations. Commanders at all levels will ensure that Soldiers operate according to the law of war and the rules of engagement (see FM 27-10). FM 3-39 uses joint terms where applicable. Selected joint and Army terms and definitions appear in the glossary and the text. Terms for which this manual is the proponent (the authority) are marked with an asterisk (*) in the glossary. Definitions for which this manual 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. FM 3-39 applies to the Active Army, Army National Guard/Army National Guard of the United States, and U.S. Army Reserve unless otherwise stated. The proponent for this manual is the U.S. Army Maneuver Support Center of Excellence (MSCoE), and the preparing agency is the U.S. Army Military Police School (USAMPS).