The Marine Corps and the Navy are conducting a series of experiments to explore the ESG and ESF concepts. As noted, the ESG concept combines the capabilities of surface action groups, submarines, and maritime patrol aircraft with those of Amphibious Ready Groups and Marine Expeditionary Units (Special Operations Capable) to provide greater combat capabilities to theater combatant commanders.[1] An Expeditionary Strike Force (ESF) integrates the CSG and ESG with the sea-basing functions provided by the Maritime Prepositioning Force (future) to provide an even more potent capability.