For some time this game was going to be a midquel to Metal Gear Solid 2 and Metal Gear Solid 4. However after Kojima Productions teamed up with Platinum Games, the story became a sequel to Metal Gear Solid 4.
Hideo Kojima, creator of the Metal Gear series, has said that a sequel to this game is possible, but only if Platinum Games develops it, saying "no one else could"
Originally this game was planned to be a back-story on the Cobra Unit from the Snake Eater game, until it was decided to be a game focused on Raiden's cyborg form.
Platinum Games' first team up with Kojima Productions.