Introduction: Language learners’ discourse, the theme of this volume, is approached in this chapter from the viewpoint of content and language integrated learning, known as CLIL (e.g. Coyle, Hood & Marsh 2010). The context is Finland, with data from secondary level history classes taught in English. More specifically, this chapter explores learner discourse in a hitherto underexplored context: group-work situations where students are involved in peer discussions without the presence of the teacher. While reaching a research-based understanding of the dynamics of teacher-student interaction in CLIL settings continues to be important for the whole CLIL enterprise and a goal worth pursuing further, it is also worthwhile to direct an analytical gaze at group-work situations and at learners’ joint processes of negotiation and interaction, because we know less about the value of these contexts for learning. What further characterizes this chapter is that rather than focusing on how students learn or how well they master the target language as a system (i.e. paying attention to the correctness of formal aspects of language), the purpose is to explore what students’ group-work interaction reveals about content and language integration, a crucial concern in CLIL given its dual and overlapping goals. In so doing, it seeks to investigate students’ joint processes of meaning making and the extent to which their discursive practices reveal any orientation to subject-specific language use. The focus is thus on the very notion of subject and language integration, how students co-construct understanding of a subject-specific activity, and the type of language this requires. Theoretically, the study is based on a discourse-pragmatic orientation to interaction which emphasizes both the necessity of situated exploration of the details of talk and attention to the social-interpersonal dimensions inherent in any communicative encounter (for more details, see Nikula 2005, 2008). As regards the approach to learning, the study draws on socio-constructivist understandings of learning, according to which it is useful to see learning as social accomplishment and meaning making as a joint construction rather than a process undertaken solely by individuals (e.g. Lantolf & Poehner 2008).