We describe a technique to manage pre-written lines of dialog by treating a conversation as a game. Thinking of conversation as a game means structuring it as a series of moves, made according to rules, with some sort of score. Speakers in our system converse by participating in short dialog trees, and make “moves” by negotiating transitions between trees. Speakers have internal state variables which describe their standing in the conversation and their emotional state. Speakers try to manage the conversation so as to maximize a payoff function of their internal variables. We believe that this technique will allow us to create lifelike NPC dialog, and allow our NPCs to play a more social role in game worlds. We also believe that games in general desperately need to have more socially coherent NPCs, and that improving dialog is a critical problem in game development. Keywords artificial intelligence, believable characters, dialog management, games