The workings of the European Union are regulated by treaties. A treaty is an international agreement made by and between the member states. All the member states of the European Union must approve each treaty. Consequently, the EU can only operate in areas in which it has competence under a treaty. The treaties are renewed when necessary. The decisions on treaties and any changes to them are made by the member states unanimously.

The treaty defines the European Union’s values and principles. It also determines the EU’s obligations and decision-making procedures. The treaty also defines the relationship between the EU and the member states and the states’ powers.

The latest treaty of the European Union was signed in Lisbon in 2007. The Treaty of Lisbon took effect in 2009. The new treaty authorised the European Union to make international agreements. The objective was to merge the European Community with the European Union so that there would only be one organisation with legal personality. After the Treaty of Lisbon the European Community was wound up on 1 December 2009.

Signing of the Treaty of Lisbon in 2007. Photo: European Parliament

The treaties consist of four founding treaties and other complementary and detailed agreements.

Treaties and legislation

The treaties define the issues on which the EU institutions may legislate. The member states put the laws passed by the EU into effect in the individual countries. The Commission cannot propose bills regarding matters that are not within its powers under a treaty. According to the treaties the EU may issue recommendations, regulations and directives. The regulations obligate the member states immediately. The directives set binding objectives for member states but they may themselves decide how to go about achieving them.