In this article we compare the resource flows of Chile, Ecuador, Mexico, and Peru between 1980 and 2000. Our objective is to analyze the structure of social metabolism of extractive countries and the consequences of the neoliberal economic structural reforms on the use of natural resources. In two decades, the domestic extraction of materials increased considerably in the four countries, mainly due to the mining sector in Chile and Peru, biomass and oil in Ecuador, and construction minerals in Mexico. Imports and exports also increased, because of the increasingly deeper integration in international markets, prompted by liberalization policies implemented in the four countries between the late 1970s and the late 1990s. All four countries had a negative physical trade balance for most of the period analyzed, with exports exceeding imports in terms of weight. However, parallel growth of imports reduced the physical deficit in Chile, Mexico, and Peru. Ecuador's physical deficit was the highest and did not decrease during the last two decades. A diversification of exports away from bulk commodities could be observed in Chile and Mexico and to a lesser extent in Peru, whereas in Ecuador the export sector remained mainly based on oil and biomass. More research is needed to explore the environmental and social impacts of the neoliberal economic reforms. Also, the indirect flows associated with direct physical imports and exports deserve to be subjected to further analysis.