This article is in the wake of a recurring problem in regional development: the disparities. Because of its vast size and small population, Canada is characterized by the persistence of disparities that tend to occur with greater acuity in the areas to the east. Restigouche is in this perspective. Located in northern New Brunswick, this area is characterized by the persistence of many socio-economic disparities compared to the province. In fact, this region is experiencing chronic unemployment, low income levels, high dependence on government transfers, a weakening of its service infrastructure as well as the depopulation of its territory. In addition, the crisis in the lumber sector seriously affected the regional economy, largely dependent on the exploitation of timber. How do local actors perceive their socio-economic situation ? This is the main question of this article that aims to analyze, from the perspective of social representations, and the issues and challenges of sustainable territorial development. Our conceptual framework is based on the concepts of sustainable territorial development and social representations. In terms of methodology, results are drawn from data from Statistics Canada and interviews. The results of our study show an accentuation of socio-economic disparities between 1986 and 2006. Although the assessment of the causes for these disparities differs considerably among actors, they unanimously admit that their persistence is difficult to reconcile with sustainable territorial development and believe that these disparities should be resolved by government.