Trade theorists and policymakers have until recently ignored trade costs, but as tariffs have fallen it is apparent that trade costs are a significant obstacle to trade and they are not simply determined by geography or commodity characteristics. We analyse country-by-country variations in trade costs using disaggregated Australian import data. In Australia average trade costs are about 5% of the value of imports, compared to an average tariff of under 4%. Controlling for distance from Australia and the bulkiness of commodities, the paper examines other determinants of international trade costs in terms of exporting country characteristics. Country-specific characteristics which influence the size of trade costs may provide a direct link between institutions and economic growth.