Commodity price booms, as those recorded in the last decade, may have a signifi-cant economic impact in small, commodity exporting, developing countries. Whether the impact on output is positive or negative is still unclear. It depends on various factors, notably on the impact that commodity prices can have on the real exchange rate of the commodity exporting countries. Two recent papers show that the real exchange rate ap-preciates when commodity prices increase. Our analysis produces new estimates of this relationship by focusing on a large sample of developing countries which are specialized in the export of one leading commodity. By using non-stationary panel techniques robust to cross-sectional-dependence, we find that the price of the...