Games are one of the most popular multiuser applications currently in use on the Internet. They have become so in spite of the lack of Quality of Service (QoS) guarantees offered by the current Internet, which are typically believed to be a requirement for delay-sensitive multimedia applications such as games. Understanding how networked games have become popular is therefore important for designing applications that can become successful with or without the presence of QoS guarantees. One reason for the popularity of games may be the interaction between players in a multiuser game. It is this interaction that compels users to play a networked game, since without other players there is little benefit to the networked component of the game. Players may be willing to tolerate lower QoS if they are able to enjoy a game with other users. This thesis examines users' preferences for one QoS parameter, delay, in networked First Person Shooter (FPS) games. We consider a player's absolute delay (the delay between a player and the game server), and their relative delay (the difference between a user's delay and that of the other players). We employ controlled and uncontrolled objective and subjective experiments: monitoring of publicly-available game servers, group experiments, a survey of game players, and controlling the delay to servers for the FPS game, Half-Life. We find that users are drawn to game servers where they can interact with a greater number of players. Delay has a greater effect on a player's decision to join a game than to leave, and a player's tolerance for delay increases with the time that they remain in the game. Although they believe relative delay to be important, in practice users are more concerned about absolute than relative delay, and can find it difficult to accurately distinguish their relative delay.