Changing farming practices is a major issue for sustainability. Such change is difficult to bring about because of strong lock-in effects within the agri-food system. Scholars have mobilized diverse approaches to address the issue of changes in agriculture, including the multi-level perspective (MLP). However, the mechanisms through which "niches" can contribute to regime reconfiguration are still unclear. In this article, we combine the diachronic and systemic approach from the MLP with insights from French pragmatic sociology and from the Alternative Food Networks literature. We analyse the trajectories of four initiatives, which can be considered as niches, as they associate various actors and develop radical innovations. Comparing their trajectories allows us to identify a generic pattern in niche development and niche-regime interactions. We identify regime reconfiguration mechanisms common to all four case studies. Niche activities and the enrolment of new actors lead to a gradual reconfiguration of the regime: first, through the construction of shared visions of agri-food issues and of the associated network of relevant actors; second, through their embedding in local policies and public action.