The Skoll World Forum was set up by eBay founder, Jeff Skoll to pursue his optimistic vision of a sustainable world of peace and prosperity. But can the world's most pressing problems be solved by investing in, connecting, and celebrating social entrepreneurs and innovators?

This year the forum will be attended by key speakers such as Bono, Atul Gawunde, Michael Porter and Don Henley. Tom Heap will be reporting from Oxford to ask whether there are reasons for optimism in poverty, health and conservation as we face fresh challenges from climate change and political uncertainty.

Producer: Helen Lennard.