Dr David Kessler, former head of the America's Food and Drug Administration, on obesity.
Former Taliban spokesman Abdul Salam Zaeef talks about Afghanistan today.
Virus hunter Nathan Wolfe thinks we can prevent future pandemics
German sex-worker Stephanie Klee says prostitution should be a job like any other.
Nike executive Charlie Denson says wearing trainers can be inspirational.
Robert Harris says the fall of the Roman republic has a chilling ring for America today
Michael Lewis on the few outsiders who bet against the sub-prime mortgage business and won
Kate and Gerry McCann on how they have coped since their daughter Madeleine disappeared
Brazilian photographer Sebastiao Salgado on the social changes of our time.
Ray Kurzweil thinks human ingenuity will eventually find a way to overcome death.