Enhanced cooperation

In the European Union (EU), enhanced cooperation (previously known as closer 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 October 2017, this procedure is being used in the fields of the Schengen acquis, divorce law, patents, property regimes of international couples, and European Public Prosecutor 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, at that time known as closer 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. At the same time, it stipulated that acts adopted within an enhanced cooperation do not form part of the Union acquis that new member states have to adopt. It also renamed closer cooperation to enhanced cooperation. The Treaty of Lisbon extended cooperation to include defence and additionally envisions the possibility for establishment of a permanent structured cooperation in defence. A minimum requirement of nine member states was also introduced. The provisions governing enhanced cooperation are now detailed in the Treaty on European Union (Article 20) and Treaty on the Functioning of the European Union (Article 326-334). The Schengen Agreement adoption is considered a historical inspiration for formalising the mechanism of Enhanced cooperation.