Developing countries traditionally experience pass-through of exchange rate changes that is greater and more rapid than high-income countries experience. This is true equally of the determination of prices of imported goods, prices of local competitors’ products, and the general CPI. But developing countries in the 1990s experienced a rapid downward trend in the degree of pass-through and speed of adjustment, more so than did high-income countries. As a consequence, slow and incomplete pass-through is no longer exclusively a luxury of industrial countries. Using a new data set - prices of eight narrowly defined brand commodities, observed in 76 countries - we find empirical support for some of the factors that have been hypothesized in the literature, but not for others. Significant determinants of the pass-through coefficient include per capita incomes, bilateral distance, tariffs, country size, wages, long-term inflation, and long-term exchange rate variability. Some of these factors changed during the 1990s. Part (and only part) of the downward trend in pass-through to imported goods prices, and in turn to competitors’ prices and the CPI, can be explained by changes in the monetary environment - including a fall in long-term inflation. Real wages work to reduce pass-through to competitors’ prices and the CPI, confirming the hypothesized role of distribution and retail costs in pricing to market. Rising distribution costs, due perhaps to the Balassa-Samuelson-Baumol effect, could contribute to the decline in the pass-through coefficient in some developing countries.