This article develops a multiscale institutional framework to shed light on the territorial dynamics of a sector. The case of the long-term transformation of the European dairy industry shows that, within a common European regulatory system, sectoral communities are structured territorially in Germany and nationally in France. Second, a change in public policies exerts pressure not only on firms’ adaptation capacities but also on sectoral communities. Third, territorial institutions appear primary in structuring sectoral dynamics when territorial players (public, private and collective) create, pool and sustainably manage productive resources, either for integration into a wider market or for developing a local means of competing.