Metal Gear Solid 2: Sons of Liberty is a 2001 action-adventure stealth video game developed by Konami Computer Entertainment Japan and published by Konami for the PlayStation 2. Originally released on November 13, 2001, it is the fourth Metal Gear game produced by Hideo Kojima, the seventh overall game in the series and is a sequel to Metal Gear Solid (1998). An expanded edition, titled Metal Gear Solid 2: Substance, was released the following year for Xbox and Windows in addition to the PlayStation 2. A remastered version of the game, Metal Gear Solid 2: Sons of Liberty - HD Edition, was later included in the Metal Gear Solid HD Collection for the PlayStation 3, Xbox 360, and PlayStation Vita. The HD Edition of the game was included in the Metal Gear Solid: Master Collection Vol. 1 compilation for Nintendo Switch, PlayStation 4, PlayStation 5, Windows, and Xbox Series X/S, which was released on October 24, 2023.

A stealth game is a type of video game in which the player primarily uses stealth to avoid or overcome opponents. Games in the genre typically allow the player to remain undetected by hiding, sneaking, or using disguises. Some games allow the player to choose between a stealthy approach or directly attacking antagonists, but rewarding the player for greater use of stealth. The genre has employed espionage, counter-terrorism, and rogue themes, with protagonists that are special forces operatives, special agents, secret agents, thieves, ninjas, or assassins. Some games have also combined stealth elements with other genres, such as first-person shooters and also platformers.