Eureka (often abbreviated as E!, or Σ!) is an intergovernmental organisation for research and development funding and coordination. Eureka is an open platform for international cooperation in innovation. Organisations and companies applying through Eureka programmes can access funding and support from national and regional ministries or agencies for their international R&D projects.

As of March 2018, Eureka has 41 full members, including the European Union (represented by the European Commission), one partner country (South Korea) and five associated members (Argentina, Canada, Chile, South Africa, Singapore). All 27 EU Member States are also members of Eureka.

Eureka is not an EU research programme, but rather an intergovernmental organisation of national ministries or agencies, of which the EU is a member. Cooperation and synergy are sought between Eureka and the research activities of the EU proper, such as with European Union's Horizon 2020 and the European Research Area.