This chapter attempts to analyze the emergence of dialogical positions within mediated social contexts by looking at how the task and, in particular, the different phases of a problem-solving task influences the repertoire of positionings. In this perspective, positioning theory is applied to analyze interactions within an exclusively text-based virtual environment called multiuser dimensions (MUDs), where textual actions and conversation are combined. MUDs are computer-meditated games based on the creation of virtual worlds for social interaction. A problem-solving task was implemented in a MUD called TecfaMoo located on the server of the University of Geneva, which is used mainly for educational purposes. The concept of interlocution scenario is based on a strong communicative interactionism perspective where personal identification is always related to the interlocutors’ features and to the aim of the interaction. This approach forces researcher to take into accounts both the conversational style and goals of each interlocutor and to consider each interaction in its uniqueness.