This project addresses the reciprocal relationship between population and environment in the Amazon Basin. We consider the influences of the changing demography of households on land use and the influences of the biophysical environment on the fertility and migration behaviors of household members in a spatially-explicit fashion. A number of variables have been found to mediate between population and environment, requiring detailed examination of this complex, reciprocal relationship. In this project we will survey 952 households in two adjacent study areas, Altamira and Santarem, Para State, Brazil that allows us to study not just the behavior of the first generation of settlers in the frontier (Altamira) but also second and third generation dynamics (Santarem). We make intensive use of Landsat satellite digital data time series from 1972 to the present; a GIS overlay of the property boundaries in the region that permits a one-to-one relating of households to land use changes, as well as transportation, hydrologic, and topographic information; and a georeferenced survey of the 952 households that examines land use and deforestation decisions and the demography of households. The research will address intergenerational population-and-environment dynamics, the impact of climate changes on deforestation choices, and the differences in land use and labor allocation choices made by rural and urban residents.