Former working-class neighbourhoods of Paris were characterized by an interaction between work and housing, especially in some big courtyards and passage ways stemming from their rural origins. In the " faubourg Saint-Antoine " (in the 11th and the 12th districts), these courtyards specialized in the wood industry, and those of the " faubourg du Temple " (in the 10th and 11th districts) in metalwork. The progressive de-industrialisation of the centre of Paris left these courtyards almost empty in the eighties and nineties, and gentrification took them over, either spontaneously or by real-estate investment. In the first case, the social transformation was progressive as the middle classes moved in and gentrified their properties; in the second case, the renovation led to the comprehensive replacement of the former working-class population by the middle and upper middle classes. In these renovated courtyards, the gentrifiers have introduced a new way of life with its own specific patterns of collective sociability. Even though they have developed few social links in the neighbourhoods in which they live, they value this mode as a strategy of social separation; it remains to be seen whether this will lead to the emergence of a fully fledged social group.