Economies are built on infrastructure. But stretched public finances mean the state is increasingly looking to the private sector to help fund infrastructure. Climate change, technological progress, and geopolitics are changing the sort of infrastructure we need. And building physical infrastructure can be fraught with hurdles from the planning process. On this episode, Paul Diggle speaks with Bridget Rosewell, board member of the UK Infrastructure Bank and former Commissioner of the National Infrastructure Commission, about the economics of infrastructure.