By Paul Reynolds
World Affairs Correspondent, BBC News website
The election of Romano Prodi's coalition will mean - barring a successful challenge to the result - a shift to the left in Italian foreign policy, and an end to the policies of personality conducted by Silvio Berlusconi.
Romani Prodi: A change of style
Mr Prodi is not a flamboyant figure. So there will not be the unpredictable fireworks of the Berlusconi era.
He is an experienced politician who has come a long way from his days as professor of industrial policy at Bologna University. He has beaten Mr Berlusconi before, in the election of 1996 (though his government lasted for only two years) and later he became European Commission president.
More EU, less US
Again, assuming that his coalition will take and keep power, he will steer Italy back towards a closer relationship with the European Union and away from the US. He strongly opposed the invasion of Iraq and expressed his view in 2004 that Europe might have prevented it.
"If Europe had been present and united, I believe we would not have seen the war on Iraq," he said.
You can discount that as the maybe unrealistic belief of a Euro federalist but of his conviction that Europe does better when it does things together, there is no doubt. He strongly supported the development of the euro, the proposed constitution, which was voted down by France and the Netherlands, and a common European foreign policy.
Farewell Silvio: An end to politics of personality
However, neither constitution nor common foreign policy will come soon, if at all, and so Mr Prodi's ambitions for Europe are not going to be fulfilled. And according to the Financial Times "the centre-left's arrival in power in Italy and the weakening of the centre-right government in France [will] do nothing to bolster the cause of reform at the European Union level."
Peter Ludlow chairman of Eurocomment in Brussels said that Mr Prodi had much to do to repair his reputation among fellow EU leaders: "Romano Prodi's problems in holding an unruly coalition together are obvious enough," he said. "He will also have to do something however to compensate for the damage that his five year stint as President of the European Commission did to his international credibility. After a brief honeymoon in 1999, he was widely regarded as very ineffective. The appointment of Mario Monti, the former Competition Commissioner, or Tommaso Padoa-Schioppa, a former Director of the European Central Bank, as his minister of finance, would however help enormously."
In addition, Mr Prodi might have to spend most of his time repairing Italy's economy in any case.
"He will not go far left so it will be a centrist, moderate left government," said Paola Subacchi, Head of the International Economics Programme at Chatham House in London.
"The tightness of his majority and the make-up of his coalition will constrain him from carrying out all the policies that Italy needs but he will try to implement some tax cuts and create more competition and reduce labour costs.
"There will be a rapprochement with the EU and he will keep his distance from President Bush with whom Mr Berlusconi was close."
Mr Prodi, in an article in Le Monde, stated: "A stronger Europe is necessary to a balanced transatlantic partnership."
He added: "No country can manage the asymmetrical challenges of our time on its own."
Mr Prodi will also carry through the decision, already taken, to withdraw Italian troops from Iraq.
He is also likely to have rather cooler relations with Russia. Again, Mr Berlusconi liked to conduct personal diplomacy and he did so with President Putin.
"Berlusconi had a special relationship with Putin which Prodi is not prepared to endorse. This will be a significant change," said Paola Subacchi.
Relations with Russia will be less cosy
Italy at the moment is being treated as a sick man of Europe, with low economic growth and it is not clear how far Mr Prodi will be able to change things. His influence in the corridors of European power will partly depend on how far he succeeds. In the absence of a common foreign policy, that is how the EU works.
The development of European diplomacy over Iran, for example, has shown how Italy has slipped out of the "premier league". It has been France, Germany and the UK who have handled the nuclear issue negotiations.
Mr Prodi is also likely to take a sympathetic approach to the Palestinians and act as brake on those in the EU who want to confront Hamas and cut off relations as much as possible.
The Middle East peace process, such as it is, is one area where the EU does try to act together and, as far as aid is concerned, it has to do so, as the money is agreed jointly.
But the main effect perhaps is going to be one of style.
Italy seems to be heading for a period of rather dour, heads-down policies and that will be reflected in its foreign policy as well.
And of course, all this will go crashing down if the coalition does not last and given the closeness of the result it might not last that long.