Voices can be used for tutorials, to tell the story, to create drama, or to convey gameplay information. In a single-player offline game, the client makes all of the decisions about which voice lines to play, but multiplayer games are more complex because it may be necessary that all players hear the same variation of a line. This chapter presents some techniques which can be used to create a voice system which is based on an authoritative server. The server directs which lines are chosen, picks who says something, and which client should play these lines. Historically, hardware channels on a soundcard were also called voices, often in the context of a voice limit. All connected clients send their player inputs to the server with very different bandwidth and latency times. The server receives these inputs, simulates the world, and executes what the game characters might do and say.