The Territorial Cooperation Program for the Southwest of Europe (SUDOE) supports regional development through the co-funding of transnational projects by the ERDF (European Regional Development Fund).

Public actors from the Spanish, French, Portuguese and British (Gibraltar) regions can contribute to the sustainable development and growth of this southwestern European area through the implementation of transnational cooperation projects on matters such as innovation, environment, new information technologies and sustainable urban development. By working together, these regional actors help southwestern Europe to achieve the strategies established by the European Union in terms of growth, employment and sustainable development. Transnational cooperation began in this southwestern European area with the Community Initiative INTERREG III B SUDOE. Coming within the context of the Objective of the European regional policy, the INTERREG IV B SUDOE Territorial Cooperation Program is the direct successor of the INTERREG III B SUDOE Program.

After making an analysis of southwestern Europe with regard to demography, its socio-economic and environmental characteristics etc., the main objective pursued in order to develop a strategy that values its strengths and corrects its weaknesses is to consolidate southwestern Europe as an Area of territorial cooperation in the fields of competitiveness and innovation, the environment, sustainable development and spatial planning, helping to ensure a harmonious and balanced integration of its regions, within the EU objectives of economic and social cohesion.