This manual provides guidance on reconstitution. It defines reconstitution; describes the planning, training, decision making, and execution processes; and establishes responsibilities. The intent is to provide commanders facing reconstitution on the AirLand Battlefield with guidance on how to maintain maximum combat power within situational and resource constraints. Reconstitution is extraordinary action that commanders plan and implement to restore units to a desired level of combat effectiveness commensurate with mission requirements and available resources. It transcends normal day-to-day force sustainment action. However, it uses existing systems and units to do so. No resources exist solely to perform reconstitution. The manual gives information to commanders and staffs who provide combat service support in regeneration operations. It also informs commanders and staffs of all types of units what support is likely available in regeneration and what their responsibilities are. The manual is applicable to all theaters and levels of command. The principles are adaptable to all levels of conflict intensity at the operational and tactical levels of war. However, the primary focus of this manual is the regeneration of battalions and brigades.