A multinational military organization comprised of Brazilian, Japanese, US and European units, through which the four powers provide for the protection of Gateway. Its units are stationed in and around Gateway Corporation facilities both on Earth and in space.

Gateway's defenses include the interplanetary cruisers USS Mayaguez, RB Brasilia, Avenging Sun and the Coureur under joint command and detachments of military police and navy personnel from each of the four countris.