The present article scrutinizes the manner with which a group of three postsecondary students (in Quebec, Canada) describe the social actors concerned by the controversy surrounding cellular telephones. The study was conducted on the basis of an ethnographic approach. Participant observation was performed by the researcher for 3 hours during each of 15 weeks. The theoretical framework developed by Callon, Lascoumes, and Barthe (2001) was drawn on to show how the group assigns roles relating to public representation and the production of legitimate knowledges; in particular, it assigns to scientists the role of conducting research; to government the roles of building citizens' awareness about the risks related to cellular telephone use, protecting users, and guiding the conduct of the cellular telephone industry; and to citizens the roles of becoming/staying informed and of making limited use of cellular telephones. The study reported here also illustrates that, in the process, the group airs their views concerning the terms best suited to defining the subject of the controversy, constituting research "collectives," and disseminating knowledge. One main conclusion is that science education research projects drawing on the contributions of Callon et al. (2001) hold out considerable promise in terms of relevance and fruitfulness. (Contains 2 footnotes.)