This paper contributes to the reappraisal of the issues approached in gentrification studies. It focuses on the role of public policies in the gentrification of the Paris inner city and, in addition to presenting technical aspects, it provides a critical analysis of this phenomenon, aiming to shed light on the political meaning of public action occurring there today. The paper gives an overview of the actors, factors and spatial dynamics involved in the gentrification process since the 1980s and then focuses in more detail on public action since 2001, when the left (Parti socialiste) took over the Paris municipality. While political goals still remain relatively ambiguous, the authors of the present paper set out to clarify the global consequences of public policies in housing, public spaces and culture. In spite of the city Council's will to overhaul public policies, its action has been unsuccessful so far in stopping the gentrification process in Paris. It has indeed actually contributed to it by transforming public spaces and by the modes of cultural action implemented.