How selling citizenship is now big business

You can be born into it, you can earn it, and you can lose it. Increasingly, you can also invest your way into it.

The "it" is citizenship of a particular country, and it is a more fluid concept than ever before. Go back 50 years, and it was uncommon for countries to allow dual citizenship, but it is now almost universal.

More than half of the world's nations now have citizenship-through-investment programmes. According to one expert, Swiss lawyer Christian Kalin, it is now a global industry worth $25bn (£20bn) a year.

Mr Kalin, who has been dubbed "Mr port", is the chairman of Henley & Partners, one of the world's biggest players in this rapidly growing market. His global business helps wealthy individuals and their families acquire residency or citizenship in other countries.

He says that our traditional notions of citizenship are "outdated". "This is one of the few things left in the world that is tied to blood lines, or where you are born," he says. He argues that a rethink is very much due.

"It's super unfair," he says, explaining that where we are born is by no means down to our own skill or talent, but instead "pure luck". "What is wrong with regarding citizenship like a hip," he adds. "And what is wrong with itting talented people who will contribute":[]}