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Lisbon Treaty becomes effective


The Lisbon Treaty - brief overview of the key changes

Following ratification of the Lisbon Treaty by the Czech Republic on 3 November 2009, the Lisbon Treaty (the Treaty) has now been ratified by all EU Member States and will come into force on 1 December 2009, although some provisions will not take effect until a later date. The Lisbon Treaty amends the existing Treaties in order to make the necessary changes to allow an enlarged EU with 27 Member States to work more effectively. It also makes changes to the way in which EU legislation is proposed and adopted. The aim of this briefing is to give a brief overview of some of the main changes introduced by the Treaty.

Structure of the Treaties: TEU and TFEU

Two Treaties, the Treaty on European Union (TEU) and the Treaty on the Functioning of the European Union (TFEU) will form the foundation of the EU and both Treaties, as well as all Protocols, will have the same legal value. The TEU sets out the objectives and principles of the EU and the TFEU provides the organisational and functional details. The TEU is the current Treaty on the European Union (the Maastricht Treaty), with amendments, and the TFEU is basically the EC Treaty, also with a number of amendments. The European Union (EU) will have a single legal personality and will replace and succeed the European Community (EC). All references to 'Community' are replaced by the word 'Union'.


The Lisbon Treaty creates the role of permanent President of the European Council, replacing the current system under which the President of the European Council rotates every six months. The President will be appointed by the Governments of the Member States.

The role of the High Representative of the Union for Foreign Affairs and Security Policy has been bolstered in order to strengthen the EU's voice on the world stage. He will preside over the Foreign Affairs Council and will also be Vice-President of the Commission. A new European External Action Service will support the High Representative.

The President of the Commission will be elected by the European Parliament. The candidate will be proposed by the European Council, nominated by qualified majority. The European Parliament will also invest the whole Commission.

The Treaty currently provides for a reduction in the number of Commissioners from 1 November 2014, when their number is to be reduced to two-thirds of the number of Member States and a rotation system will operate to determine which Member State will send a Commissioner for any given term. This will now not happen, because in order to pave the way for the second Irish referendum he Council undertook (in December 2008) that once the Treaty comes into force, a decision will be made to maintain the number of European Commissioners at one for each Member State.

The European Court of Justice (ECJ) becomes the Court of Justice of the EU, and the CFI becomes the General Court. The jurisdiction of the Court of Justice is expanded to all the activities of the EU, with the exception of the common foreign and security policy. The Treaty also improves access to the European Courts for private individuals, by removing the requirement of 'individual concern' where a natural or legal person challenges 'a regulatory act which does not entail implementing measures' (this can cover certain Regulations which were previously almost impossible to challenge).

— Lexology

The Lisbon Treaty - brief overview of the key changes. Lexology.

More links

Treaty of Lisbon amending the Treaty on European Union and the Treaty establishing the European Comm...

The Treaty of Lisbon. Fact Sheets on the European Union.

Understanding the Lisbon Treaty. Foundation Robert Schuman.

The Lisbon Treaty for dummies. Irish News.

The Lisbon Treaty: A Brief Outline, by Giorgio Maganza. Fordham International Law Journal. (PDF)
The Lisbon Treaty explained
The Brief: 10 years of The Lisbon Treaty
The Brief: 10 years of The Lisbon Treaty



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Published in 30/12/2019

Updated in 19/02/2021

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