In France as elsewhere, schools are reminded of their mission to educate people for coexistence and democracy. In this context, the fight against ethnocultural discrimination has gradually become an object of teacher training. However, while new training content and a range of tools are emerging, they remain scattered and opaque. Unevenly adopted by stakeholders, this dimension of teacher training is also insufficiently linked to research. This issue aims to contribute to structuring the reflection in this area from two complementary perspectives. On the one hand, it takes advantage of research on discrimination and its accompanying school processes (segregation, evaluation or orientation bias, etc.) to identify training objects and levers. On the other hand, it reflexively scrutinises dedicated training methods in order to identify their pitfalls and potentialities. The research presented covers four contexts: French-speaking Switzerland, French-speaking Belgium, Quebec, and France. The comparison reveals the strong indexicality of these questions, both in the way in which discriminated groups are identified and problems are constructed, and in the place this subject occupies on the agenda of education and training policies. To sum up, the dossier invites to tackle the debate on ethnocultural discrimination head-on and make it an object of collective reflexivity, taking specific account of local contexts.