In Argentine agriculture, the process of "agriculturization" is associated with changes in technology, expansion of the agricultural frontier to the extra-Pampean regions, and increasing monocultures. Until the late 1930s, agricultural expansion was mainly based on expanding the agricultural frontier by occupying new lands, over 30% of total agricultural land and livestock in the humid pampas. Since the 1960s, agriculturization has been achieved at the expense of areas devoted to ranching, industrial crops, and forest lands. In the 1990s, land concentration and intensification of agriculture greatly ac-celerated, both in the pampas and in extra-Pampean regions (Northwest and Northeast). Between 1988 and 2002 an intense process of concentration of land ownership, accompanied by further agricultural conversion to soybean, took place too. The loss of native forest resources in Argentina is directly related to the expansion of the agricultural frontier. This article explains: 1) the deforestation/agricultural frontier expansion in Argentina, 2) the environmental changes caused by this process, 3) actions from social actors involved in this process.