The game was initially bundled with all retail and digital copies of Half-Life 2, before being released standalone. Each round is won either by completing an objective (such as detonating a bomb or rescuing hostages) or by eliminating all members of the enemy team.
As in the original, Counter-Strike: Source pits a team of counter-terrorists against a team of terrorists in a series of rounds. Released in October 2004 for Windows, it is a remake of Counter-Strike (2000) using the Source game engine.