"ADRP [Army Doctrine Reference Publication] 3-28 clarifies similarities and differences between defense support of civil authorities (DSCA) tasks and other tasks of decisive action. Stability tasks and DSCA tasks are similar in many ways. Both revolve around helping partners on the ground within areas of operations. Both tasks require Army forces to provide essential services and work together with civil authorities. However, homeland operational environments differ from those overseas in terms of law, military chain of command, use of force, and interorganizational coordination. This ADRP helps Army leaders understand how operations in the homeland differ from operations by forces deployed forward in other theaters. It illustrates how domestic operational areas are theaters of operations with special requirements. Moreover, this ADRP recognizes that DSCA is a joint mission that supports the national homeland security enterprise. Department of Defense conducts DSCA under civilian control, based on United States law and national policy, and in cooperation with numerous civilian partners. National policy, in this context, often uses the word joint to include all cooperating partners, as in a joint field office led by civil authorities. ADRP 3-28 is organized into four chapters. Chapter 1 explains the Army's role in the homeland. It places Army contributions to DSCA within the context of overarching national and military policies that establish a comprehensive approach for national preparedness. Chapter 2 discusses the core purposes and functional characteristics of Army contributions to DSCA. In addition, chapter 2 includes key legal considerations related to the employment of military forces in the homeland. Chapter 3 discusses how Army forces organize to achieve unity of effort. Chapter 4 describes the tasks of decisive action performed by Army forces conducting DSCA and National Guard civil support."