Faced with a clear reduction in customers since the 1990s, the French thermal towns have deployed various actions to create and perpetuate coalitions aimed at increasing their political capacity and, thereby, to revive local economy. The cases of Dax (Nouvelle-Aquitaine) and Bagnoles-de-l’Orne (Normandy) have been studied to analyse the way in which projects and their territorial marketing have bolstered the construction and the maintenance of these alliances. However, the analysis also shows how the quest for trust and the search for compromise can limit the ambitions of the strategies in question.