Ordinary legislative procedure in the context of Legislation

The Treaty of Lisbon (initially known as the Reform Treaty) is a European agreement that amends the two treaties which form the constitutional basis of the European Union (EU). The Treaty of Lisbon, which was signed by all EU member states on 13 December 2007, entered into force on 1 December 2009. It amends the Maastricht Treaty (1992), known in updated form as the Treaty on European Union (2007) or TEU, as well as the Treaty of Rome (1957), known in updated form as the Treaty on the Functioning of the European Union (2007) or TFEU. It also amends the attached treaty protocols as well as the Treaty establishing the European Atomic Energy Community (EURATOM).

Prominent changes included the move from unanimity to qualified majority voting in at least 45 policy areas in the Council of Ministers, a change in calculating such a majority to a new double majority, a more powerful European Parliament forming a bicameral legislature alongside the Council of Ministers under the ordinary legislative procedure, a consolidated legal personality for the EU and the creation of a long-term president of the European Council and a High Representative of the Union for Foreign Affairs and Security Policy. The Treaty also made the Union's bill of rights, the Charter of Fundamental Rights, legally binding. For the first time, the treaty gave member states the explicit legal right to leave the EU, and established a procedure by which to do so.