What happens to presidents and prime ministers when they stop running their countries, and leave politics behind? Giles Edwards has spent 10 years finding out what they do next. He shares some of his conversations with former world leaders, takes us inside their organisations and helps us understand their thinking. Giles begins at the Clinton Global Initiative in New York City, where he speaks to presidents and prime ministers about how they use their influence, and what they contribute when they speak out. (Photo: Bill Clinton speaks at a Clinton Global Initiative meeting in Manhattan in September 2022. Credit: David Delgado/Reuters)