Abstract We draw on household survey data from countries of all income levels and document that average unemployment rates increase with gross domestic product per capita. This is accounted for almost entirely by low—rather than high—educated workers. We interpret these facts in a model with frictional labour markets, a traditional self-employment sector, skill-biased productivity differences across countries, and unemployment benefits that become more generous with development. A calibrated version of the model does well in explaining the cross-country patterns that we document. Counterfactual exercises point to skill-biased productivity differences as the most important factor in explaining the cross-country unemployment patterns.