The reason why some countries are rich and others poor depends on many things, including the quality of their institutions, the culture they have, the natural resources they find and what latitude they're on.
Behind the scenes with the team who look after all 843 acres of Central Park, revealing the hidden systems and organisational miracles that keep the world's busiest urban park clean and green. Plus, Ant Anstead sees how an entirely new district is being built on top of a functioning rail depot in Manhattan and Dan Snow is in Coney Island, where he discovers that television, air conditioning and extreme weather almost killed off this historic amusement zone.
As we entered the 21st century, the world was guzzling oil, coal and gas like never before. Despite fears of 'peak oil', Professor Iain Stewart discovers that while huge technological advances are helping extend the life of existing oilfields, new unconventional oil and gas supplies like shale gas and tar sands are extending the hydrocarbon age well into the 21st century.
Paul Saffo looks at the development of the US economy through the 20th and into the 21st century. What are the trends that have shaped the economy? How are innovations in technology and communications making the 21st century an entirely different landscape for producers and consumers?
In the month that followed the bankruptcy of Lehman Brothers in September 2008, the world stared into the abyss of total financial collapse. The third part of the BBC's definitive series on the crash tells the extraordinary story of how politicians reacted, and asks what has been learnt from the entire calamity. Could it happen again?
The programme explains how we changed our attitude to risk, learnt to live with debt and, above all, how governments stepped back from regulating any of it. At the heart of the story is Alan Greenspan, who for 20 years was one of the most powerful people in the world. In October 2008, weeks after the catastrophic collapse of Lehman Brothers, the man whose ideas influenced the world admitted he might have been 'partially' wrong.