The Spanish CoR delegation is composed of 21 members, 17 members and alternates one from each of the 17 Autonomous Communities and 4 members and alternates from the Municipalities.

The Conference for the European Union affairs (CARUE) adopted various agreements enabling the Autonomous Communities’ direct participation in the EU institutions. Firstly, it established a rotating system among the Autonomous Communities in view of having one representative within the Spanish delegation in the meetings of the European Commission’s committees (ex-comitology). Secondly, it adopted an agreement on 9 December 2004 allowing the participation of the Autonomous Communities in the Council of the EU meetings and working groups: one member having the status of a regional minister or member of the autonomous government is allowed to participate in the Spanish delegation to the EU Council, in its formations for agriculture and fisheries; environment; employment, social policy, health and consumers; education, youth and culture. In recent years, CARUE extended the scope to the working party on Consumer Protection and Information and the working party on Establishment and Services for the gambling and betting dossiers, both within the Competitiveness Council.

Finally, two counsellors from the regional administration designated by the CARUE join the REPER (Representación Permanente de España ante la Unión Europea) as responsible for the department on autonomous affairs.

All the Autonomous Communities have liaison offices established in Brussels. Some are integrated in the REPER (Asturias, La Rioja, Aragón, Castilla - La Mancha, Madrid and Castilla y León), but many have separate offices (The Basque Country, Catalonia, Galicia, Andalusia, Cantabria, Murcia, Valencia, the Canary Islands, Navarra, Extremadura, the Balearic Islands). Moreover, the Province of Barcelona, as well as the Provinces of Badajoz and Caceres have liaison offices in Brussels.

As for the local level, the FEMP is a member of the Council of European Municipalities and Regions (CEMR) and the United Cities and Local Governments (UCLG) network. It also coordinates the Spanish participation in the Congress of local and regional authorities of the Council of Europe (CLRAE) and the Spanish local representatives of the European Committee of the Regions.

In addition, three Autonomous Communities (Catalonia, Valencia Community and Murcia Region) are members of the Assembly of European Regions (AER). All the Autonomous Communities and the Autonomous Cities of Ceuta and Melilla are members of the Conference of European Regional Legislative Assemblies (CALRE) and the Conferences of European Regions with Legislative Power (REGLEG), the first one for the regional parliaments and the second one for the regional governments.