sustainability has become a major issue within the tourism environment, urging the need to measure its economic, social and environmental variables. Agenda 21, a product of this Summit, recommends the implementation of governance processes, such as satisfaction surveys, as one of the tools for measuring sustainability. In the aftermath of the COVID-19 health crisis, sustainability will be the essential element of stability and control in the face of future crises on a global scale. This research proposes the opinion of residents and visitors as one of the bases for the design of sustainable tourism. Therefore, it analyses the level of sustainability felt by both groups, through more than 1800 satisfaction surveys carried out in Albufeira, Faro and Lagos in the Algarve - Portugal. It is perceived that the local population is satis ed with tourism, although they do not want more tourists. The tourist activity developed in the destinations is linked to the sun and beach, reaching, on the part of the tourist, a high level of satisfaction, and there is an intention to return in the coming periods. However, the surveys revealed the need for improvements in infrastructure to o er higher levels of excellence and attractiveness, which have not yet been achieved, thus strengthening o -season tourism, involving society and its idiosyncrasies.