The ability to form shared task representations is considered a keystone of social cognition. It remains, however, contentious if, and to what extent, social categorization impacts on shared representations. In the present study, we address the possibility of the modulation of action co-representation by social categorization, such as group membership and social status, as indexed by the social Simon effect. Italian participants were requested to perform a social Simon task, along with either an Italian (high-status in-group) or an Albanian (low-status out-group) participant. Results show that Italian participants co-represented the action of their partner when paired with a high-status in-group participant. Conversely, this effect was absent when they performed the task with a low-status out-group participant. Furthermore, the Albanian participants co-represented the action of their partner when paired with an Italian participant. These results suggest that group membership modulates action co-representation through the varying of the groups' relative status. The impact of this issue is boundless given the increasing multicultural nature of our society. Indeed, if multiculturalism fails, modern society does likewise.