The Schengen Agreement consists of two international treaties that have been in force since 1995:

- the Schengen Agreement of 1985 for the gradual abolition of border checks at the signatories’ common borders and

- the Convention implementing the Schengen Agreement of 1990 on a common security and asylum policy.

The Schengen Acquis (the Schengen agreements and the rules for implementing them) became part of EU law through the Treaty of Amsterdam on May 1, 1999. Since then, all new EU Member States must integrate the Schengen Acquis into their national legislation.

The Schengen Area currently consists of 22 EU Member States which have fully adopted the relevant regulations (as of February 2015): Belgium, Denmark, Germany, Estonia, Finland, France, Greece, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Austria, Poland, Portugal, Sweden, Slovakia, Slovenia, Spain, Czech Republic, and Hungary. The EU Member States of Bulgaria, Croatia, and Romania have not yet fully applied the Schengen acquis. The EU Member States of Cyprus, Ireland, and the United Kingdom of Great Britain are not parties to the Schengen Agreement but have implemented some of its regulations.

Iceland, Liechtenstein, Norway, and Switzerland have signed a treaty of association and have acceded to the acquis.

Source: Auswärtiges Amt, edited (not available in German)