The Maastricht Treaty (officially the Treaty on European Union), signed on 7 February 1992 by the members of the European Communities in Maastricht, Netherlands, created the European Union (EU); established a three-pillar structure for further European integration; and laid down the "convergence criteria" for the introduction of the euro in 2002 as a common European currency. The institutional and policy architecture established by the treaty for European economic and monetary union faced its first major challenge in the European debt crisis that unfolded from the end of 2009.
The Maastricht Treaty reformed and amended the treaties establishing the European Communities, the EU's first pillar. It renamed the European Economic Community as the European Community to reflect its expanded competences beyond economic matters. The Maastricht Treaty also created two new pillars of the EU on Common Foreign and Security Policy and Cooperation in the Fields of Justice and Home Affairs (respectively the second and third pillars), which replaced the former informal intergovernmental cooperation bodies named TREVI and European Political Cooperation on EU Foreign policy coordination.
The Maastricht Treaty (TEU) and all pre-existing treaties have subsequently been further amended by the treaties of Amsterdam (1997), Nice (2001) and Lisbon (2007). Today it is one of two treaties forming the constitutional basis of the EU, the other being the Treaty on the Functioning of the European Union.