Spain takes over the rotating presidency on 1 January, but it will be a six-month tenure with a twist, as Madrid is the first to grapple with the complexities of the EU's new legal framework.
The Lisbon Treaty entered into force one month ago, ushering in a new layer of governance in the European Union - a permanent president of the European Council - but keeping the old system of rotating presidencies, only with a less prominent status.
It will be up to Spain's prime minister, Jose Luis Rodriguez Zapatero, to see how this plays out in everyday practice so that he and Herman Van Rompuy, the newly appointed EU president, are neither publicly nor internally stepping on each others' toes.
Under the new system, Mr Zapatero and his government will be responsible for the day-to-day running of the bloc, including chairing nearly all of the monthly ministerial meetings in Brussels. Mr Van Rompuy's job will be to represent the EU externally at summits and to give political impetus to the regular meetings of EU leaders.
The treaty leaves plenty of scope for potential turf wars: Spain has said that it would like to host the EU-US and Latin America summits, in a move that will propel Mr Zapatero into the global spotlight alongside Mr Rompuy. The possibility of having Barack Obama on Spanish soil for a summit is already sparking protocol speculation, such as who will be the first to shake the US leader's hand.
However, Spain has also been careful to make overtures in the run up to the New Year when it starts the presidency and Mr Van Rompuy formally takes up his duties.
"You will have the rotating presidency at your disposal ... so that you can properly carry out the function of leadership, the political management of the European Council," said Mr Zapatero earlier in December.
"My first objective during the six months is that there is institutional consolidation" and "clear visibility for the highest function that the Lisbon Treaty gives to the president of the European Council," he added.
Spain will have to do much of the behind-the-scenes legwork in working on the proposal with member states and MEPs.
Madrid also wants to have financial supervision laws approved during its presidency, running to 30 June.
Member states in December agreed to set up three pan-European watchdogs to supervise banks, insurers and trading exchanges. Another agency is to look out for wider risks to the economy. The broad agreement will now have to be turned into workable EU legislation
Another task will be how to take forward the vague and not very ambitious international agreement on climate change from the Copenhagen meeting in mid-December. The first step will be taken by the European Commission which will issue an analysis of the outcome for a ministerial meeting on 15-17 January.
As with most presidencies, the Spanish are bringing their own particular issues to the EU negotiating table – in Madrid's case tackling gender violence.
Diego Lopez Garrido, Spain's Europe minister, said the country wants an EU law to protect against gender violence and wants a "non-discrimination directive" approved under its watch as well.
Spain's presidency will also be affected by the fact that the European Commission will be mostly out of action for at least part of January as it waits for the new commissioners to be approved by the European Parliament. In addition, the parliament itself, newly elected since June, has yet to really cut its legislative teeth.
And while there will be interest to see how much of the its ambitious agenda it can actually implement during its six months at the tiller, Madrid's enduring legacy is set to be the template it writes for how future rotating presidencies should function under the Lisbon Treaty.