This article provides an empirically based perspective on the contribution of conversation analysis (CA) and sociocultural theory to our understanding of learners' second language (L2) practices within what we call a strong socio-interactionist perspective. It explores the interactive (re)configuration of tasks in French second language classrooms. Stressing that learning is situated in learners' social, and therefore profoundly interactional, practices, we investigate how tasks are not only accomplished but also collaboratively (re)organized by learners and teachers, leading to various configurations of classroom talk and structuring specific opportunities for learning. The analysis of L2 classroom interactions at basic and advanced levels shows how the teacher's instructions are reflexively redefined within courses of action and how thereby the learner's emerging language competence is related to other (interactional, institutional, sociocultural) competencies. Discussing the results in the light of recent analyses of the indexical and grounded dimensions of everyday and experimental tasks allows us to broaden our understanding of competence and situated cognition in language learning.OVER THE LAST 2 DECADES, IT HAS BECOME more and more accepted within such different fields as cultural anthropology, language acquisition, and developmental psychology that learning processes, and more generally cognition, have something to do with social interaction. The problem, of course, remains how to pin down that something, that is, how to identify, both theoretically and empirically, the exact contribution of the interactional dimension to learning.This embedded nature of cognitive development in social practices has been the focus of study in two intellectual frameworks. During the last 2 decades, studies undertaken in conversation analysis (CA), as well as in the sociocultural and sociocognitive frameworks, have provided empirical evidence suggesting that the social realm cannot be reduced to a mere background factor in relation to which activities, including cognitive processes, take place, but is an integral part of cognitive development itself. This view has been captured by the notion of situated learning (Lave & Wenger, 1991), according to which learning is rooted in the learner's participation in social practice and continuous adaptation to the unfolding circumstances and activities that constitute talk-in-interaction. Situated learning invites us to look from a new perspective at what the learner is doing when he or she engages in a specific task or activity in a given socio-institu-