After French and Dutch voters rejected the proposed Constitution for Europe in referenda in 2005, the EU entered into a “period of reflection” to try to work out what to do next. It was clear that the grandiose-sounding constitution was not likely to win approval from voters any time soon. On the other hand, many EU governments insisted that an enlarged EU still needed the changes that the constitution would have brought about, especially to its decision-making processes. So the idea emerged of a “reform treaty” that would drop words like flag, anthem and well, constitution, but would still enable the EU to reform its creaking institutions. The treaty was signed in Lisbon in December 2007. Crucially, the idea was that most countries would be able to ratify it by a simple parliamentary vote rather than a referendum. In the end, Ireland, the only country whose constitutional arrangements obliged a referendum on Lisbon, rejected it once (in June 2008) before giving it the nod in a second vote in October 2009. Ratification was completed in early November and the treaty entered into force on December 1 of that year.

Amongst other things, the treaty extended Qualified Majority Voting in the Council of Ministers, allowed for a reduction in the number of commissioners (but with a get-out clause), gave the EU legal personality, beefed up the position of the EU high representative for foreign policy and scrapped the rotating presidency of the European Council in favour of a system whereby one senior political figure chairs all summit meetings for two-and-a-half years.