On 2 October 1997, in Amsterdam, the heads of state and government of the 15 European Union member states sign the Treaty of Amsterdam, amending the Treaty on European Union and the Community treaties.

Negotiated in the 1996–1997 Intergovernmental Conference, the treaty strengthens the common foreign and security policy, integrates the Schengen Agreement into the EU framework, reforms justice and home affairs cooperation, and prepares the institutions for enlargement.

The document was signed by all then members; it entered into force on 1 May 1999 after national ratifications. It remains an intermediate step between Maastricht (1992) and Nice (2001) / Lisbon (2007).

The consolidated text is published in the Official Journal and on EUR-Lex.

For EU law, 2 October 1997 marks the Amsterdam signature.

The document is available on EUR-Lex.

The Treaty of Amsterdam of 2 October 1997 remains the milestone of pre-enlargement institutional reform.

Image: Amsterdam; Wikimedia Commons. Cropped to 16:9.

Source consulted: Treaty of Amsterdam. Treaty text: EUR-Lex — Treaty of Amsterdam.