Researchers investigating Network-based Language Teaching (NBLT) seldom relate to Computer Supported Collaborative Learning (CSCL), an important field in educational research which strongly stresses the value of group learning, adopting socio-cultural Vygotskian and Brunerian views. As a result, the concept of collaboration is scarcely deepened or problematized by NBLT researchers. However, choosing between collaborative or non collaborative learning settings when designing a distance learning course has a strong influence on tutor involvement. This paper explores the issue, thus attempting to bridge the gap between NBLT and CSCL. It does so by qualitatively analyzing online interactions in several distance learning courses (collaborative and non collaborative) and by examining these verbal exchanges in the light of collective activity, learners' social autonomy, and tutor role and involvement. The methodological approach is qualitative and consists in analysing, a posteriori, online interactions between learners and tutors.<br />After having defined the theoretical framework, the authors compare structures of online interaction in two pre-service teacher courses, focusing on the role of the tutor and on the issue of student autonomy. Finally, they examine more precisely some features of collaboration, analyzing tutor and student interactions in an online language course.