Reunion Island in the Indian Ocean is experiencing rapid socio-economic change. The spatial component of this change was mapped using Spot images between 1989 and 2002. The change detection method used is a comparison of classifications (maximum likelihood and structural analysis). The results confirm a rapid increase in urban spread, a spatial migration of agricultural activities from lowland to upland areas and sharp disparities between micro-regions. The analysis also reveals more pronounced trends in midland and upland areas and, surprisingly, inside the current boundaries of the National Park. These results challenge some regional development assumptions on Reunion Island, particularly the idea that urbanisation is spreading exclusively into agricultural areas.