Based on an on-line survey and interviews with users, this article analyses the forum of the Italian Radical Party. This forum has several specific characteristics (high attendance rate, intense vitality of the debates, and the obligation to be identified) and fulfils various functions: source of information, place of training and political activism, and a 'community'? which strengthens radical links. Regarding its deliberativeness, the forum is perceived by participants as inclusive and egalitarian, and as a place where opinions sometimes change. However, about one third of the respondents perceived the forum as 'hardly'? or 'not at all'? respectful.