Can doughnuts save the planet?

Imagine a ring doughnut. This is the basis of an idea about how we could run the world in a way that gives everyone what they need - food, homes, healthcare and more - and save the planet at the same time. Economist Kate Raworth, who came up with the idea, explains how it works. And we visit projects in Amsterdam that are using the model to provide food, clothing and sustainable housing. Produced and presented by Anna Holligan.