ESPON

Interreg is a series of five programmes to stimulate cooperation between regions in the European Union, funded by the European Regional Development Fund. The first Interreg started in 1989. Interreg IV covered the period 2007–2013. Interreg V (2014-2020) covers all 28 EU Member States, 3 participating EFTA countries (Norway, Switzerland, Liechtenstein), 6 accession countries and 18 neighbouring countries. It has a budget of EUR 10.1 billion, which represents 2.8% of the total of the European Cohesion Policy budget. Since the non EU countries don't pay EU membership fee, they contribute directly to Interreg, not through ERDF.

Interreg is designed to stimulate cooperation between member states of the European Union on different levels. One of its main targets is to diminish the influence of national borders in favor of equal economic, social and cultural development of the whole territory of the European Union.

The Interreg initiative is designed to strengthen economic, social and territorial cohesion throughout the European Union, by fostering the balanced development of the continent through cross-border, transnational and interregional cooperation. Special emphasis has been placed on integrating remote regions with those that share external borders with the candidate countries.

Interreg was launched as Interreg I for the programming period 1989–1993 (budget EUR 1.1 billion), and continued as Interreg II for the subsequent period 1994–1999. It moved on to Interreg III for the period 2000–2006. Projects from that closed by the end of 2008. Interreg IV is currently operational, covering 2007–2013.

Interreg differs from the majority of Cohesion Policy programmes in one important respect: it involves a collaboration among authorities of two or more Member States. Interreg measures are not only required to demonstrate a positive impact on the development on either side of the border but their design and, possibly, their implementation must be carried out on a common cross-border basis.

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