The perimeter of “urban remembrement” (PRU in French) is a Walloon tool introduced in June 2006. It was created in the philosophy of operational urban planning, in a context of urban renewal. Its objectives are to promote urban regeneration and to simplify administrative procedures. Early research about the tool demonstrated that, in fact, the use of the PRU doesn’t seem as efficient as hoped to reduce transaction costs (time delays) of an urban remembrement operation. Furthermore, it highlighted two modes of appropriation of the tool by actors: an “opportunity strategy” and a “proactive strategy”. The purpose of this master’s thesis is to verify the findings of the initial research in the field, as well as to make an overall assessment of the tool while the current Planning Act (CWATUP) is going to be replaced by the CoDT. The methodology includes an analysis of PRU’s approved administrative records and semi-structured interviews with key informants. The results confirm the first findings in terms of reduction of time delays and show the emergence of a new strategy of appropriation. Moreover, it appeared during the research that the use of the PRU tool seems to have been jeopardized in recent years, following a stance of jurisprudence. Tool improvement proposals are issued at the end of the paper. ; Le périmètre de remembrement urbain (PRU) est un outil d’aménagement wallon mis en place en juin 2006. Il a été créé dans la philosophie de l’urbanisme de projet, dans un contexte de reconstruction de la ville sur la ville. Ses objectifs sont de favoriser le renouvellement urbain et de simplifier les procédures administratives. Les premières recherches sur l’outil ont démontré que, dans les faits, l’utilisation du PRU ne semble pas aussi efficace qu’espéré pour réduire les coûts de transaction (délais) d’une opération de remembrement urbain. De plus, elles ont mis en évidence deux formes d’appropriation de l’outil par les acteurs : une stratégie proactive et une stratégie d’opportunité. La mission de ce mémoire est ...