The Affordable Housing Crisis

London, New York and Mumbai - three cities where the cost of buying or renting a home is out of reach for many. Why can't the market supply more affordable housing?
Manuela Saragosa speaks, among others, to Stephen Howlett, head of the Peabody Trust - a charity that provides affordable homes in London - to Daniel Bentley of right-wing thinktank Civitas, who advocates limiting foreign investors from buying up property in the UK, and to Adam Challis, head of residential property research at the British property managers Jones Lang LaSalle.
Meanwhile Jonathan Woetzel of consultants McKinsey explains why this is a global phenomenon affecting cities both rich and poor.