Amsterdam Treaty

Amendment to the founding treaties of the European Union (EU) adopted at the Amsterdam European Council in June 1997, signed on 2 October 1997, and in force from 1 May 1999. The treaty provided for the further protection and extension of the rights of citizens; new mechanisms to improve the coordination of the EU's common foreign and security policy; and the strengthening of the EU institutions (extending the co-decision procedure by which legislative proposals need the agreement of both the Council of the European Union and the European Parliament).