The United States maintains 13 maritime pre-positioning ships, in 3 squadrons, in 3 separate areas around the world. Each squadron can equip and support 1 MEB (Marine Expeditionary Brigade) for 30 days of combat operations. Maritime pre-positioning ships are Roll-on/Roll-off (Ro-Ro) type ships; they are capable of off-loading their cargo without the need for elaborate port facilities. The Marines will be flown into a secure area where they will equip from the pre-positioning ships.

One squadron of 5 ships is stationed at Diego Garcia, in the Indian Ocean; a second at Guam and Tinian (4 ships), and the third, also with 4 ships, at a site yet to be determined in the Eastern Atlantic (for operations in Europe).