The European Environment Information and Observation Network (Eionet) is a partnership network of the European Environment Agency (EEA) and its 38 member and cooperating countries. The EEA is responsible for developing Eionet and coordinating its activities together with National Focal Points (NFPs) in the countries.

The NFPs are responsible for coordinating networks of National Reference Centres (NRCs), bringing together experts from national institutions and other bodies involved in environmental information.

Eionet also includes seven European Topic Centres (ETCs). They are consortia of institutions across EEA member countries dealing with a specific environmental topics and contracted by the EEA to perform specific tasks of its work programme.