Infrastructure networks are a key feature of an economy. Their functionality depends on the connectivity and sizes of different components and they face a variety of threats, from natural disasters to intelligent attacks. How should networks be defended and designed to ensure the best functionality?

Biographical note: GoyalSanjeev: Sanjeev Goyal is professor of economics at the University of Cambridge and a fellow of Christ’s College. He is one of the pioneers in the economic study of networks, and his work has appeared in leading international journals such as "Econometrica, Journal of...