During my Master's degree "Townplanning, Housing and International Cooperation", I wrote a research about "Spatial Identity" in renewal urban project's neighboorhoods on Reunion Island. The aim of the study was to understand if the evolutions, induced by housing programmes, may influence actors representations and practices in these spaces. The subject of my PHD is the logical continuum of these considerations. I work actually about "Alterity" as potential tool for local development. Based on Reunion Island, I have a CIFRE contract and work more especially on questions about territorial amenities, the potential of local and integrated development, the rural and mountain space's dynamics and about the concepts of Identity / Alterity applied to Reunion Island rural and montain territories.