The desire to accelerate economic growth and to optimize the allocation of factors of production has led some of the world's largest agro-export nations to strongly support the liberalization of the international agro-food trade. However, protection and regulation are still prevalent in a great number of countries where agriculture accomplishes functions other than the production of commodities for internal consumption or export. The latter concern self-sufficiency, food security, occupational roles, management of the environment and support for industrial development. The aim of this paper is, taking national input-output tables as the starting point, to propose a methooology for the analysis of the relations between international trade and the internal structures of agro-food systems. The hypothesis is that indiscriminate liberalization, especially if "export-oriented", leads to the homogenization of techniques, the specialization of agriculture and filiéres, and, finally, to an extraverted economy. All these factors operate against the globalization of exchange in agriculture. Well-oriented protectionism, on the other hand, leads to the diversification of production and international exchange. It also favors the expansion of agro-industrial complexes, the diffusion of technical change and the internalization of the benefits of agricultural growth. The analysis of the Chilean case is very instructive in this respect. Here, an attempt will be made to evaluate the impact of the progressive shift from import-substituting to export-oriented industrialization after 1973 on the national agro-industrial complexes.