Will immigration matter in France's presidential election?
Always in the background, immigration has so far not been as prominent an issue as it was in 2007.
Back then, Sarkozy actively tried to attract sympathisers of the far-right Front National but polls show that many who voted for him then, intend to go back to their old party this time.
However, their old party is trying to change. New leader Marine Le Pen (daughter of Jean-Marie) has re-vamped the Front National's image.
She talks less of immigration, much more about protecting French jobs and industry, the problems of the euro and the negative effects of globalisation.
Sarkozy’s so-called “immigration choisie” policy was inspired by the systems in Canada and Australia, where quotas are set to attract immigrants to work in sectors where jobs are unfilled, such as the construction industry.
He was criticised when he tightened the rules on immigration for family reasons and for foreigners wishing to work after graduating in France.
Socialist François Hollande was asked in a TV programme whether he would continue Sarkozy’s policy. After much equivocating he said he favoured “immigration intelligente” without specifying what he meant.
The subject of immigration in France is inextricably linked to the place of muslims in society.
France colonised several north and west African countries, and many people from these countries later settled in France where they and their children now make up Europe’s largest muslim population.
Sarkozy’s presidency saw two major initiatives in this area: a debate on national identity which was widely seen, even by supporters of the idea, as divisive, damaging and unproductive; and the ban on wearing a burka in public places, which polls show was a popular reform.
In fact, most immigrants to France come from European Union countries, so France has little control over them. When Sarkozy sent back Romanians living in illegal camps in France, creating a huge furore, the majority returned a few months later.
The question of whether foreigners living in France should be allowed to vote in local elections (EU citizens already can) has been pushed up the political agenda.
Sarkozy and Marine Le Pen are opposed to the idea, Hollande and Bayrou are in favour.
This is a country which has long attracted immigrants from the poorer parts of Europe and from former colonies - it's estimated that one in four French citizens has a grandparent born outside France- but with less money around and challenges surrounding the French system of strict separation between religion and state, surveys suggest that attitudes have hardened in recent years.