Rethink... the future of cities

The United Nations estimates that nearly half of mankind will live in cities by 2050.

And as those cities have grown, the number of people living in slums has also increased. The UN estimates that 1.2 billion people reside in so-called “informal settlements”, mostly in low and middle income countries.

But what if you could build brand-new cities, offering economic opportunity for migrants? What if those cities were built by attracting foreign investment and entrepreneurs, and importing "better" laws, making it easier to operate a business and generate wealth?

That's the idea behind Charter Cities, the brainchild of the Nobel-prize winning economist Paul Romer. He was inspired by the massive growth of Hong Kong and Shenzhen in China. Both cities raised living standards in just two generations, by adopting market-led reforms.

He described it as a global win-win situation. So are these new cities potential utopias of opportunity and innovation? Or are they budding dystopias, where democracy means nothing, and the poor toil at the whim of the ultra-rich?

Presenter: Ben Ansell Producer: Ravi Naik Editor: Justine Lang

Contributors: Atossa Araxia Abrahamian, journalist and author of "The Hidden Globe: how wealth hacks the world". Tom W Bell, law professor and consultant on alternative governance, special economic zones, and open-source law. Dr Mark Lutter, founder and executive chairman of the Charter Cities Institute. Dr Sam Wetherell, Senior Lecturer in the History of Britain and the World at the University of York, and expert in Urban History.