The Assembly of European Regions (AER) is a network, partner and voice for European regions, connecting regional communities and supporting cooperation across Europe since 1985. Based in Brussels, Strasbourg and Alba Iulia, it brings regional priorities into discussions on European policy and advocates on issues including sustainable development, inclusion and EU cohesion policy. AER also helps members share knowledge through mutual learning, working groups, knowledge transfer and peer-learning activities.

Its programmes and projects address topics such as skills, youth participation, circular systems and intercultural cooperation, while its events provide opportunities for regions and partners to exchange experience and develop connections. Activities include the AER Summer Academy, the Youth Regional Network and the Intercultural Regions Network. Through Eurodyssey, AER offers paid traineeships in European regions.

The organisation also publishes activity reports, policy positions and other resources, and hosts meetings such as its General Assembly and regional forums. AER invites regions to join its network and take part in collaborative initiatives