This field manual (FM) provides keystone Army doctrine for civil support operations. It expands on the discussion of civil support operations, the fourth element of full spectrum operations, in FM 3-0. This manual focuses on the planning, preparation, execution, and assessment of civil support operations, which are conducted within the United States and its territories. It discusses the role of Army forces cooperating with and supporting civilian organizations in domestic operational environments, with particular emphasis on how operations conducted by Army forces within the United States...