Since the 1980s, museums have been gradually used within the framework of vast programs of urban regeneration initiated by the public authorities. In cities, heavily marked by industry, public authorities think that the opening of a museum on their territory could improve image and attract investors or companies. This article tries to assess the territorial impact of three museums located in the territories of old manufacturing areas in Europe: Imperial War Museum North (Manchester), the Museum of Design (Essen) and the Museum of Contemporary Arts or MAC' S (Mons). If museums enable the physical transformation of the city and the improvement of its image, the economic and social impacts of museums, chronically overdrawn institution, are very limited outside sectors of tourism and the culture. Museums don’t completely achieve its goal of democratization, neither inside its walls nor its direct urban environment.