The French society has experienced during the 1945-1980 période an abrupt transition to a new economic and social model. Cities have been the recipient and the way of these changes. The large housing estates were the magnifying mirror of the structural weaknesses caused by this change. That’s why they are a good place to observe the emergence and treatment of social and environmental vulnerabilities caused by urban transformations taking place since 1945. Different categories of the population have been deeply weakened by the considerable construction effort : workers of the building trade facing a new work environment due to the industrialization of the sites, people confronted with new housing deficiencies and specificities of life in these new neighborhoods, residents upset by the radical change in their environment ... We study especially the residents of the large housing estates, showing how construction public policies put those people toward a new and pathogenic environment. This process have its origine in the experimental development of new construction methods after the Second World War. Their important risks were early identified. In spite of these problems, the new construction methods are widely extended and massified through the construction of large housing estates in 1950’s and 1960’s. Very quickly politicians and city professionals saw that the people were exposed to significant physical and psychic risks. The remedial public policies often seem delayed, partial and undersized to face such structural big failures.