This paper provides an overview of the concept of computer supported collaborative learning (CSCL). While there is no clear shared conceptualisation of the field at the moment, some interesting issues concerning the nature of collaboration and the role of computers in supporting it are identified. The perspective of the paper is heavily influenced by the socio-cultural school of psychology. Several examples of CSCL are discussed briefly and problems and opportunities for CSCL identified. The need for the further study of learning in settings outside the classroom is stressed.