This paper addresses the question of environmental change in Amazônia, by looking at the experiences of the large-scale biosphere-atmosphere (LBA) experiment in the Amazon, and three other enterprises-the extractive reserves, the Pilot Programme to Conserve the Brazilian Rain Forest (PPG7) and ecological-economic zoning-that address questions of sustainable development in the region. The LBA experience shows how the integration with the social sciences can be critical for science to explore its own outcomes for society, while the other programmes expose environmental change as a problem with too many intersections within society, so the outcomes of any initiative depends on placing it before a complex, tense and wide arena.