Commodity markets are critical to the global economy. Creating policy frameworks that support the economic goals of sustainable growth, inflation stability, poverty reduction, food security, and climate change mitigation necessitates an understanding of what drives market developments. This is the first comprehensive examination of market and policy developments for all commodity groups over the last century, including energy, metals, and agriculture. Although the amount of commodities consumed has increased significantly due to population and income growth, their relative importance has changed over time as a result of new uses for some materials enabled by technological advancement and the ease with which commodities can be substituted. The research shows that commodity markets are diverse in terms of economic drivers, price behaviour, and macroeconomic effects on emerging and developing economies. It also demonstrates that the relationship between economic growth and commodity demand varies significantly across countries depending on their stage of economic development. Policy structures that allow for countercyclical macroeconomic responses are more prevalent – and beneficial – than ever. Other policy tools have yielded a variety of outcomes.