After years of conducting counterinsurgency operations centered on forward operating bases (FOBs), the Army and Marine Corps have introduced a new operational concept to operate, fight, and campaign successfully in the 2025 to 2040 time frame. The concept, called “Multi-Domain Battle: Evolution of Combined Arms for the 21st Century,” is generating discussion across the joint logistics enterprise. Its focus is how sustainers can best support U.S. forces in tomorrow’s combat.