National audience Three tracks are invested in this thematic section: — The first is to grasp the symbolic dimension of the centre of work. To what extent does the labour movement provide grammar for collective action? To what extent does collective action in the 68s involve defining itself in particular in relation to the trade union movement, not only against it, in order to differentiate itself, but also positively, through the reownership of its repertoires of action, organisation and symbolisation? How does the inflation of labour class speeches contribute to calling into question the legitimate monopoly of the Communist Party and the CGT so far? — The second approach leads to the study of this centrality in its socio-spatial dimension. The centre of labour is that of industrial sites in social conflict. Some factories constitute places of investment for various activists (gauchists, Christians, feminists, etc.), both because of the attention paid to them by external activists and by the opening-up practices which are developing in the course of new forms of conflict and occupation. The return of these mobilisations to a given site makes it possible to identify the contribution of non-workers to industrial conflict, as well as the way in which the links between intellectuals and workers are established. It also makes it possible to look for the traces of mobilisations excluded from the legitimate pleadings of the dispute: what about, for example, a worker feminist? Finally, a third runway concerns the loss of working centrality in its diachronic dimension: working more precisely on the centre of work is also about the conditions for its weakening, a more detailed chronology that may vary locally. It is a question of calling into question the common idea of a sudden changeover, a crisis which has taken place from the end of the 1970s, in order to trace the more precise linearths and prolongations. In addition to the public representations of the collapse of the working class and its organisations at the turn of the 1980s, there is still a working group, but considerably reconstituted, and there are still labour struggles: how do they fit into their environment in the following decades? The multitude of possible multipliers — activists, political, cultural, media, etc. — who have lost or won, who still have them?