Recent increase in the rate of deforestation of the Brazilian Amazon has inflamed discussion about the causes of forest loss, with a special focus on agriculture. This paper studies the expansion of agriculture in the Brazilian Amazon from 1976 to 2001 based on the eight most important products (cattle, bananas, beans, cassava, coffee, maize, rice and soybeans). A biological delimitation of the Amazon based on a map of Brazil's biomes was adopted in order to avoid inclusion of non-forested areas in the analysis. Intense spatial changes in Brazilian agriculture have occurred, with the emergence of new production centres for soybeans and cattle. Several of these regions are located nearby or inside the Amazon's limits. Livestock and soybean cropping in Brazil are consistently moving north. The contribution of the Amazon to Brazilian agriculture rose significantly during the last decades, reaching 28.9% of cassava, 21.3% of banana, 14.2% of rice and 20.0% of cattle production in Brazil in 2001 (three-year average). Cropped area and production in the Amazon have grown at higher annual rates than in the rest of the country for almost all items analysed, supporting the view that the region is a new frontier of Brazilian agriculture. Most recent trends point to a vigorous demand for new land, which will consequently imply a predicted increase in forest clearing.