ATHENA is a mechanism which administers the financing of common costs of EU operations having military or defence implications. It does so on behalf of EU Member States contributing to the financing of EU military operations.

The mechanism was set up by the Council of the European Union in 2004 and its legal basis was amended in 2011. Currently four active EU military operations benefit from ATHENA financing, which is provided by 27 Member States: EUFOR ALTHEA, EUNAVFOR ATALANTA, EUTM SOMALIA and EUTM MALI.

ATHENA manages the financing of common costs for these operations, which can include transport, infrastructure, and medical services, as well as the Nation Borne Costs, which include lodging, fuel, and similar costs linked to the national contingents.