This paper reports on the findings of a case study that set out to discover student behaviour in the computer room while the participants were engaged in a collaborative computer-assisted language learning (CALL) task in form of an electronic role-play which was designed for advanced learners of business German. The task mainly utilized information and communication technologies (ICTs). Data was collected using screen-capturing software that also recorded the oral interactions between students while they were completing the task. For the analysis two methods were applied: First, grounded theory methods facilitated capturing categories that can describe student behaviour. Second, a case study approach facilitated emerging vignettes to become visible which could be reported on separately. The study showed strategies students employed when dealing with problems, manifestations of collaboration, different working modes and steps in text production, as well as student focus on form. This project's findings contribute to the interest in study of student behaviour in computer-room learning tasks (Levy & Michael, 2011) as well as to the discussion about students' expression of their agency (Van Lier, 2008). Furthermore, they contribute to the discussion about useful methodologies and methods involving screen-capturing software. [For the complete volume, see ED574893.]