This chapter describes an online video teleconferencing tool the authors have created that allows learners to collaborate, negotiate, discuss, share ideas and emotions, and establish relationships while engaged in educational games and simulations. The ENJEUX-S (L’Environnement multimédia évolué de JEUX éducatifs et de Simulations en ligne) multimedia environment relies on Web Services for the management and operation of online games and simulations and on real-time communication services (audio- and video-conferencing, chat) to support a collaborative working environment for players. The authors first describe the components of ENJEUX-S, their technological choices, and the environment’s architecture. Then, they present the results of ENJEUX-S testing to correct problems and measure ease of use and functionality for target users. Finally, they outline the pedagogical contributions of such an environment in the context of online games and simulations, notably to development of interpersonal competencies including cooperation, communication, and teamwork.