© World Economic Forum

Collier, a professor at Oxford University, is best-known for his influential book The Bottom Billion, in which he examined the failures of international aid to developing countries. In his 2013 book, Exodus, he turned his attention to global migration.

Further reading:

Cracking down on tax avoidance
Without China on board, Africa will supper, writes Collier.

How much is enough?
For too long we have allowed xenophobes to set the terms of the immigration debate, Collier writes.

The “bottom billion”
Collier delivers his TED talk on the poorest billion people in the world.