Should Britain stay in the EU or opt for a so-called "Brexit" - a British exit.
BI caught up with Publicis Groupe CEO Maurice Lévy at Davos to pick his brains on the topic.
Publicis Groupe is a France-based
So what does Lévy make of a possible Brexit?
In some respects, he believes Prime Minister David Cameron has done the right thing by calling a referendum because even if Britain stays within the EU, the maneuver to threaten an exit will have given him leverage when negotiating other deals and terms with Europe.
"We all know the Brits are keen on bargaining - it's far better than the Turkish bazaar - and they will get a pound or two of flesh," Lévy said. "The problem is that it will be at the expense of European solidarity and will be opening all sorts of negotiations which are not really very good for Europe."
Lévy said he couldn't imagine a Europe without the UK and he doesn't want the Brexit to happen. He believes British companies will suffer too.
"It will be more damaging for the British companies than for the European companies because what will happen is they will not be able to close the borders in the UK and they may lose a lot of advantages that they already have," he added.
The EU referendum was announced by Prime Minister David Cameron almost exactly two years ago today. For two years, countless hours have been spent discussing and lobbying for either side of the vote - time Lévy feels could have been better-spent.
"I think what is a pity is that instead of using all this energy to build a better Europe and to bring all the countries together, this approach, which is a little bit selfish, is not serving the interest of Europe," Lévy said.
"We need a Europe which is more unified, and we need more Europe rather than less Europe. And we need David Cameron, who has a voice which is extremely strong in Europe, working in favor of bringing the countries together rather than only thinking about the UK."