Wolfenstein: Enemy Territory is an online multi-player game, wherein the players interact with each other over a network, in two teams (Allies and Axis) to defend or destroy mission objectives.The game is playable over the Internet or a Local Area Network. Like many online games, cheating and exploit communities exist. To counter this, the game has support for PunkBuster, an anti-cheat solution.

There are six officially released maps that are partially based on real locations or events (North African Campaign: Gold Rush, Siwa Oasis, and Atlantic Seawall Battery; Europe Campaign: Rail Gun, Würzburg Radar, and Fuel Dump),as well as hundreds of custom maps made by the Internet community.On each map, the offense needs to complete a certain set of objectives within a limited amount of time. The defense needs to keep the offense from completing objectives until time runs out. Some objectives may be optional, and some objectives can be carried out by either team. These minor objectives assist the team completing them. Depending on game mode the action will continue on another map (Campaign Mode) or the same map (Objective Mode, Stopwatch Mode, Last Man Standing).