This publication provides joint doctrine for the conduct of amphibious operations. This publication provides fundamental principles and guidance to assist joint force commanders (JFCs), their staffs, and supporting and subordinate commanders in the planning, execution, and assessment of amphibious operations. An amphibious operation is a military operation launched from the sea by an amphibious force (AF), embarked in ships or craft with the primary purpose of introducing a landing force (LF) ashore to accomplish the assigned mission. An AF is an amphibious task force (ATF) and an LF together with other forces that are trained, organized, and equipped for amphibious operations. Amphibious operations apply maneuver principles to maritime power projection in joint and multinational operations. Amphibious operations can be designed to achieve operation or campaign objectives in one swift stroke; comprise the initial phase of a campaign or major operation to establish a military lodgment; serve as a supporting operation to deny the use of an area or facilities; to fix enemy forces and attention; to outflank an enemy; or to support military engagement, security cooperation, deterrence, humanitarian assistance, and civic assistance. AFs provide the JFC with a tailored, mobile force that is flexible enough to facilitate the entry of follow-on forces, be the main or supporting effort, or accomplish a coup-de-main. Amphibious operations take place across the range of military operations and are categorized into five types: assaults, raids, demonstrations, withdrawals, and amphibious support to other operations. An amphibious assault involves the establishment of an LF on a hostile or potentially hostile shore. An amphibious raid is a type of amphibious operation involving swift incursion into or temporary occupation of an objective followed by a planned withdrawal. An amphibious demonstration is a show of force conducted to deceive with the expectation of deluding the enemy into a course of action (COA) unfavorable to it. An amphibious withdrawal is the extraction of forces by sea in ships or craft from a hostile or potentially hostile shore. This publication has been prepared under the direction of the Chairman of the Joint Chiefs of Staff. It sets forth joint doctrine to govern the activities and performance of the Armed Forces of the United States in joint operations and provides the doctrinal basis for interagency coordination and for US military involvement in multinational operations. It provides military guidance for the exercise of authority by combatant commanders and other joint force commanders (JFCs) and prescribes joint doctrine for operations, education, and training. It provides military guidance for use by the Armed Forces in preparing their appropriate plans. It is not the intent of this publication to restrict the authority of the JFC from organizing the force and executing the mission in a manner the JFC deems most appropriate to ensure unity of effort in the accomplishment of the overall objective. Joint doctrine established in this publication applies to the Joint Staff, commanders of combatant commands, subunified commands, joint task forces, subordinate components of these commands, and the Services.