Economic success‐​among individuals, firms, products and countries‐​is often unexpected and unpredicted. William Easterly will draw on insights from Nobel laureate Friedrich Hayek to explain why prediction is difficult, success is rare and failure is common; the advantages of decentralized decision making to discover what works best in the market and in public policy; and the need to rely on dispersed and local knowledge, rather than government planning, for poor countries to achieve growth.