The objective of this article was to map disparities in the increases of agricultural areas in the Brazilian mesoregions between 1994 and 2013; particularly the levels of concentration of soybeans, corn, and cotton. The methodological approach included Cluster procedures and locational Gini coefficients. The results highlighted a frontier line identified in the central-northwest area of Brazil. As for the crops, a more concentrated expansion of the agricultural area dedicated to cotton was verified in the selected mesoregions. This expansion was less concentrated in soybeans and even less concentrated in corn.