1 Supplementary information to “Amazon Conservation Scenarios” Roads to be paved The most important determinant of future patterns of deforestation in the Amazon (defined as the Amazon river watershed, the Legal Amazon in Brazil, and the Guiana region) is the paving and construction of highways. Several paving projects are currently planned by the Brazilian government. A 700-km section of the BR-163 highway is slated for paving from the border of Mato Grosso and Pará states to Itaituba, linking the soy production region of Mato Grosso with the river transport system of the Amazon. Other paving projects planned for the Brazilian Amazon include the BR-230 (Transamazon Highway), BR-319 (Manaus- Porto Velho Highway), BR-156 from Amapá state to French Guyana, BR-401 from Roraima state to Guiana, as well as many others of secondary importance (Fig. S1). Outside of Brazil, highway paving is planned across the Andes, linking the lowland Amazon with Pacific ports including Callao in Peru and Arica in Chile. One of these highways links Assis Brasil, in Acre, Brazil, to Puerto Maldonado and Cuzco or Puno in Peru; the other would link Cruzeiro do Sul, Acre, via Pucalpa, to Lima. Paving is also planned for the road from Cárceres, Mato Grosso state in Brazil to Santa Cruz city in Bolivia (Fig. S1). Santa Cruz is a burgeoning population center located inside the Amazon Basin with economic importance even greater than the capital La Paz owing to its large natural gas fields. The Cárceres-Santa Cruz corridor would become the shortest route linking the industrial and highly populated southeastern Brazil, through its agro-business central region, to the Pacific Ocean. The impacts of proposed highway paving on land use change, migration patterns, and the human populations that already live along these roads will depend upon the effectiveness of regional planning processes currently underway 1 . Other infra-structure investments are also contemplated for the Amazon, including river channelization for fluvial transportation, port construction, hydroelectric plants, and gas pipelines 2,3,4 . Our analyses focus on the effect of road-paving on future trajectories of land-use change, since the effects of other infra-structure investments is highly uncertain. To incorporate the influence of this planned road paving into the simulations, we established a schedule of likely dates at which paving will be completed based upon analyses of government documents and conversations with government officials, setting the years of completion of