Field Manual FM 3-38 Cyber Electromagnetic Activities provides overarching doctrinal guidance and direction for conducting cyber electromagnetic activities (CEMA). This manual describes the importance of cyberspace and the electromagnetic spectrum (EMS) to Army forces and provides the tactics and procedures commanders and staffs use in planning, integrating, and synchronizing CEMA. This manual provides the information necessary for Army forces to conduct CEMA that enable them to shape their operational environment and conduct unified land operations. It provides enough guidance for commanders and their staffs to develop innovative approaches to seize, retain, and exploit advantages throughout an operational environment. CEMA enable the Army to achieve desired effects in support of the commander's objectives and intent. The principal audience for FM 3-38 is all members of the profession of arms. Commanders and staffs of Army headquarters serving as joint task force or multinational headquarters should see applicable joint or multinational doctrine concerning cyberspace operations, electronic warfare (EW), and spectrum management operations (SMO). Trainers and educators throughout the Army will also use this manual. United States (U.S.) forces operate in an increasingly network-based world. The proliferation of information technologies is changing the way humans interact with each other and their environment, including interactions during military operations. This broad and rapidly changing operational environment requires that today's Army must operate in cyberspace and leverage an electromagnetic spectrum that is increasingly competitive, congested, and contested. FM 3-38, Cyber Electromagnetic Activities, is the first doctrinal field manual of its kind. The integration and synchronization of cyber electromagnetic activities (CEMA) is a new concept. The Army codified the concept of CEMA in Army Doctrine Publication (ADP) 3-0, Unified Land Operations, and ADP 6-0, Mission Command. The mission command warfighting function now includes four primary staff tasks: conduct the operations process (plan, prepare, execute, assess), conduct knowledge management and information management, conduct inform and influence activities (IIA), and conduct CEMA. The purpose of FM 3-38 is to provide an overview of principles, tactics, and procedures on Army integration of CEMA as part of unified land operations. At its heart, CEMA are designed to posture the Army to address the increasing importance of cyberspace and the electromagnetic spectrum (EMS) and their role in unified land operations. CEMA are implemented via the integration and synchronization of cyberspace operations, electronic warfare (EW), and spectrum management operations (SMO). FM 3-38 contains seven chapters: Chapter 1 defines CEMA and provides an understanding of the fundamentals of the CEMA staff tasks. It briefly describes each activity and provides a framework for the emerging operational environment that includes cyberspace. Chapter 2 begins with a discussion of the commander's role in the conduct of CEMA. It then describes the CEMA element, its role in the operations process, and how it interacts with, supports, and receives support from other staff members. Chapter 3 provides tactics and procedures specific to cyberspace operations. Chapter 4 provides tactics and procedures specific to EW. Chapter 5 provides tactics and procedures specific to SMO and the functions executed by the spectrum manager. Chapter 6 describes how CEMA are executed through the operations processes, including other integrating processes. Chapter 7 describes considerations unique to CEMA when conducting operations with unified action partners. Appendix A provides guidance on CEMA input to operations orders and plans.