Infrastructure systems play a vital role in economic and social development. Demand for infrastructure is set to continue to expand significantly in the decades ahead, driven by major factors of change such as global economic growth, technological progress, climate change, urbanisation and growing congestion. However, challenges abound: many parts of infrastructure systems in OECD countries are ageing rapidly, public finances are becoming increasingly tight and infrastructure financing is becoming more complex. This book assesses the future viability of current "business models" in five infrastructure sectors: electricity, water, rail freight, urban mass transit and road transport. It proposes policy recommendations that aim to enhance capacity to meet future infrastructure needs, including measures that could be taken by governments both collectively and individually to create more favourable institutional, policy and regulatory frameworks.