community of practice; computer-mediated communication; discourse community; face; ingroup; membership categorization; online discussions; relational work; verbal antagonism

Based on a corpus of internet discussions on medical topics, this study examines a salient characteristic of the genre - the prevalence of aggressive verbal antagonism. Drawing on concepts of face, rapport management and relational work, I argue that the effects of verbally aggressive behaviour in this genre are not only destructive and anti-social, but also perform a constructive function, offering benefits both to individual speakers and to the discourse community as a whole. The analysis shows how speakers target different aspects of their opponents? face, deploying a range of face attack strategies (moves). The study then seeks to demonstrate how aggressive facework can help speakers construct and enhance their own face, as well as functioning as a stimulus to constructive relational work among participants.