Enhanced cooperation

In the European Union (EU), enhanced cooperation is a procedure where a minimum of nine EU member states are allowed to establish advanced integration or cooperation in an area within EU structures but without the other members being involved. As of February 2013 this procedure is being used in the fields of divorce law and patents, property regimes of international couples and is approved for the field of a financial transaction tax.

This is distinct from the EU opt-out, that is a form of cooperation between EU members within EU structures, where it is allowed for a limited number of states to refrain from participation (e.g. EMU, Schengen Area). It is further distinct from Mechanism for Cooperation and Verification and permanent acquis suspensions, whose lifting is conditional on meeting certain benchmarks by the affected member states.

Enhanced cooperation was introduced by the Treaty of Amsterdam for community, judicial cooperation and criminal matters. The Treaty of Nice simplified the mechanism and forbade opposition to the creation of enhanced cooperation. It also introduced cooperation for the Common Foreign and Security Policy, except for defence matters. The Treaty of Lisbon extended cooperation to include defence and additionally envisions the possibility for establishment of a permanent structured cooperation in defence.

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