It is just eight weeks before many of us take part in a moment of British history - the vote on whether we want our country to remain in or leave the EU.
But how might the choice to leave or remain affect security at home or immigration in the future?
ITV News Political Editor Robert Peston investigates.
- Free market and free movement
A fundamental principle of the European Union - enshrined in the 1992 Maastricht Treaty - is that European citizens should be able to live and work anywhere within the bloc without restriction.
But despite its advantages it has become one motive for wanting to leave the EU because of a frustration at the large number of EU migrants coming to live in Britain.
Since 2004, the number of EU migrants living in the UK has been rising steadily.
On the other hand, remain advocates extol the advantages of freedom of movement.
Those who would prefer to leave hope for something quite different.
- Economic benefits and disadvantages
Paul Johnson, managing director of Transervice haulage company, favours staying in the EU.
Those who favour remaining say hard working migrants boost our economic growth – and that European immigrants pay more in UK taxes than they take out in benefits and public services.
But leave argue it’s a strain on these resources we can no longer cope with - and there’s a fear that an expanded EU that include - say Turkey or even the Ukraine - would mean even more people coming to live and work here.
On the other hand 1.2 million Brits currently take advantage of the freedom of movement to live and work in the EU, so what would happen to them if we left?
It remains an open question, but there may be reciprocal arrangements with those countries and they will fall to be negotiated on a country by country basis.
While both sides of the battle agree we need immigrants to keep our economy ticking over, the arguments over how many, where they come from and what skills they should have before being let in will be at the centre of the EU referendum debate right up until polling day.
Tonight: Europe - In or Out? will be broadcast on Thursday at 7.30pm on ITV.
Is this a subject that will be influencing how you vote in the referendum? Tweet us at @ITVTonight