Who is more affected if Britain leaves the EU: the South African student living in the UK for six months or the German who has lived there and paid taxes for fifteen years? The Indian working in the City for a couple of years before moving back to Mumbai, or the British pensioner who retired to Spain in 2002?
Some time in the next year or two there will be a referendum on whether the UK leaves the EU.
In a bizarre anomaly, if you're one of the million people from the rest of the Commonwealth living in the UK, you will likely be given the vote (as you are in general elections) - but you won't if you're one of the 2.3 million people from another European country, or if you are British and have lived outside the UK for more than fifteen years.
As I left the UK in 2003 I'll probably get the vote if the referendum is held in 2017, but it will be a close-run thing. Millions of others who moved slightly longer ago will be deprived of a say.
If you're one of the 2.2 million Brits who lives in another EU country, it might not always feel like Europe made your move easier.
When I came to Sweden I was made to line up at the Migration Board office with everyone else for a stamp in my passport. That certainly didn't feel like free movement (they've streamlined things since then, I hear); in Italy, one British woman told us how she was made to wait two years for her official paperwork to be sorted out.
But, in reality, these hurdles are minor compared with what non-Europeans face. And our rights are part and parcel of the European project.
Just ask a non-European about their experiences at the visa office. One Canadian friend who split up with her boyfriend recently found that in addition to dealing with the emotional fallout, the split meant she lost her visa - and with it her right to work over here.
Ah, some people say, but Britain will negotiate a good deal if it leaves. Look at Norway or Switzerland - it's easy to move there.
Maybe it will, but why should EU governments give the UK - or its citizens - an easy ride if it breaks up the Union? They won't want other potential quitters to think they can have their cake and eat it by keeping the fun bits like freedom of movement, while jettisoning the boring bits like environmental legislation.
Those of us who have moved within the EU, either to or from Britain, are those who lose most if Britain quits. We've planned our lives, our loves, our jobs around an arrangement that we had every right to think would be permanent.
Yet as things stand, we are unlikely even to be consulted.
None of this is yet certain - and we won't know exactly what the government's planning until David Cameron presents the EU Referendum Bill to the House of Commons in a week or two. Then MPs will have a chance to amend and vote on the proposal.
The EU is far from perfect, God knows. It certainly needs reforming. But it has also provided opportunities for millions. Over the next few months, The Local will make sure that the voice of people who have gained most from Europe - and have most to lose if Britain quits - are heard loud and clear.