Communication is a critical aspect of any collaborative system. In online multiplayer games and virtual worlds it is especially complex. Users are present over long periods, require both synchronous and asynchronous communication, and may prefer to be pseudonymous or engage in identity-play while managing virtual and physical use contexts. Initially the only medium for player-to-player communication in virtual worlds was text, a medium well suited to identity-play and asynchronous communication, less so to fast-paced coordination and sociability among friends. During the past decade vendors have introduced facilities for gamers to communicate by voice. Yet little research has been conducted to help us understand the influence of voice on the experience of using virtual space: Where, when, and for whom voice is beneficial, and how it might be configured. To address this gap we examined a range of online gaming environments. We analyzed our observations in the light of theory from Human-Computer Interaction, Computer-Supported Cooperative Work, and Computer-Mediated Communication. We conclude that voice radically transforms the experience of online gaming, making virtual spaces more intensely social but removing some of the opportunity for identity play, multitasking, and multigaming while introducing ambiguity over what is being transmitted to whom. /martinrg) is a researcher working at the intersection of science technology studies and human-computer interaction with an interest in the domestic appropriation of high-speed broadband and digital commemoration; he is an Associate Professor in the