Within the growing body of work that is sometimes labeled CA-for-SLA, there is a need for more research with longitudinal data. Hellermann and Cole (2009) provide a valuable contribution in this area. However, in doing so, they also make use of an exogenous theory of learning, situated learning theory (Lave and Wenger 1991), and its associated theoretical concepts of community of practice and legitimate peripheral participation. In this response, it is argued that these concepts do not necessarily fit the data which Hellermann and Cole (2009) analyze and that situated learning theory is not appropriate for the analysis of how second/foreign language learners participate in and learn through interaction. It is further argued that the danger of importing an exogenous theory of learning into CA-for-SLA is that the analysis will come to be driven by the theory, even when the theory does not fit the data.