This article proposes to consider a coalition government not in terms of relations between elected representatives, but rather administrative inputs. It concentrates on the agents of the Bureau of City Planning in Paris, working on a new urban plan under the coalition regime between 2001 and 2008. Their work tends to dissociate effective regulatory tools and discussed topics. Therefore, it strengthens the coalition’s stability, because conflicts and compromises can unfold more easily since they have few substantial implications for the document.