Energy, transport, water and telecommunications all are essential to future development and growth. However, infrastructure investment requirements over the coming decades will be massive, running into trillions of dollars. How will the needed investments be financed, given that OECD populations are ageing fast and public finances tightening? How will such factors as urbanisation, climate change and globalisation affect the development of infrastructures in OECD countries? And how will the role of the public sector and private actors evolve over time? These are just some of the questions this OECD report addresses in this long-term assessment of the future of infrastructures in both OECD and non-OECD countries.