This publication, Field Manual FM 3-0 Operations Change 1 6 December 2017, describes how Army forces, as part of a joint team, shape operational environments (OEs), prevent conflict, conduct large-scale ground combat, and consolidate gains against a peer threat. This manual provides a foundation for how Army forces conduct prompt and sustained large-scale combat operations. FM 3-0 is applicable to all members of the Army Profession: leaders, Soldiers, and Army Civilians. The principle audience for FM 3-0 is commanders, staffs, and leaders. This manual also provides the foundation for training and Army education system curricula and future capabilities development. FM 3-0 contains fundamentals, tactics, and techniques focused on fighting and winning large-scale combat operations. This manual uses historical vignettes, quotes, and graphics to reinforce the doctrine within. FM 3-0 contains 8 chapters and 2 appendixes: Chapter 1 describes large-scale combat operations and associated challenges Army forces face today. It addresses anticipated OEs, threats, joint operations, and the Army's strategic roles in support of joint operations. The chapter then discusses unified land operations and associated topics, including decisive action, operational art, and the operational framework. Chapter 2 is divided into four sections. Section I provides an overview of Army echelons, capabilities, and training. Section II provides a general discussion of Army forces in a theater. Section III describes Army capabilities by warfighting function. Section IV addresses training for large-scale ground combat. Chapter 3 provides an overview of operations to shape the OE. It discusses operation assessments and describes threat activities prior to armed conflict. A discussion of shaping activities performed by Army forces follows. The chapter then describes Army organizations and their roles as they shape the OE. Chapter 4 provides an overview of operations to prevent conflict. It addresses assessing OEs in which Army forces conduct activities to prevent war during crisis action, and it provides a description of threats. The chapter continues with a discussion of the major activities within operations to prevent. The chapter concludes with the roles of the theater army, corps, divisions, and brigades. Chapter 5 is divided into four sections. Section I provides an overview of large-scale combat operations. Section II addresses tactical enabling tasks that apply to both the defense and the offense. Section III provides a discussion of forcible entry operations from which Army forces may defend or continue the offense. Section IV discusses the transition to consolidation of gains. Chapter 6 begins with a general discussion of the defense, followed by a discussion of how an enemy may attack. It continues with sections on planning and preparing corps and division defenses. It then addresses the three primary defensive tasks. Chapter 7 begins with a general discussion of the offense, followed by a discussion of how an enemy may defend. It continues with a section on how corps and divisions plan for the offense. This chapter then provides +a discussion of forms of maneuver and the four offensive tasks. The chapter concludes with a discussion on the subordinate forms of attack. Chapter 8 expands upon operations to consolidate gains discussed in previous chapters. It describes how Army forces transition from large-scale ground combat operations to operations that translate tactical and operational success into lasting gains. An expanded description of the operational framework and the consolidation area follows. The chapter concludes with a description of consolidation activities. Appendix A provides doctrine on command and support relationships that form the basis for unity of command and unity of effort. Appendix B provides commanders with a listing of risk considerations for the planning of large-scale ground combat.