Abstract : This article focuses on different means of constructing a scholarly on-line debate related to the field of Science Technology and Society. The study shows how scientific interactions are reproduced in a new medium while simultaneously, some users take advantage of new possibilities offered by the medium. The first section analyzes how the debate emerged, was constructed, and subsequently revealed the heterogeneity of goals and ideas among the participants. The second section discusses the practices that the participants explored to make the debate evolve. Two attitudes, identified as strategic and tactical, were observed. The tactical practices were to enable the emergence of a sense of community. From this perspective, the way some participants sustained mobilization and stimulated participation are analyzed. The strategic attitude is illustrated through the behavior of those who tried to be the leaders in the debate.