EU treaties

Treaties of the European Union
Front page of an EU document containing the consolidated treaties and documents which comprise the legal basis of the EU
Location	Italian Ministry of Foreign Affairs
Purpose	Establishing the laws and principles under which the European Union is governed

The Treaties of the European Union are a set of international treaties between the European Union (EU) member states which sets out the EU's constitutional basis. They establish the various EU institutions together with their remit, procedures and objectives. The EU can only act within the competences granted to it through these treaties and amendment to the treaties requires the agreement and ratification (according to their national procedures) of every single signatory.

Two core functional treaties, the Treaty on European Union (originally signed in Maastricht in 1992) and the Treaty on the Functioning of the European Union (originally signed in Rome in 1957 as the Treaty establishing the European Economic Community), lay out how the EU operates, and there are a number of satellite treaties which are interconnected with them. The treaties have been repeatedly amended by other treaties over the 65 years since they were first signed. The consolidated version of the two core treaties is regularly published by the European Commission.

The two principal treaties on which the EU is based are the Treaty on European Union (TEU; Maastricht Treaty, effective since 1993) and the Treaty on the Functioning of the European Union (TFEU; Treaty of Rome, effective since 1958). These main treaties (plus their attached protocols and declarations) have been altered by amending treaties at least once a decade since they each came into force, the latest being the Treaty of Lisbon which came into force in 2009. Lisbon also made the Charter of Fundamental Rights legally binding, though that is not a treaty per se. The troubled ratification of Lisbon has meant there is little climate for further reform in the next few years beyond accession treaties, which merely allow a new state to join.