This study assesses the future carbon dioxide emissions in the global material flow of primary aluminium. The model of the global aluminium industry (GlobAl model) is used for scenario calculations. It simulates a market economy and allows an integrated analysis of the material flow and the corresponding carbon dioxide emissions. 1995 is the base year and the future horizon of the scenario calculations is 2010. The critical parameter 'global demand for primary aluminium' is varied. According to the scenario calculations, the absolute carbon dioxide emissions in the global material flow of primary energy will not increase until the growth rate of demand reaches 2% per year. World average specific emissions will decrease remarkably, especially due to the reduced energy-related emissions for smelting. There are three reasons for this. In the first place, the lower CO2-emission factor of electricity generated from fossil fuels leads to reduced emissions. Secondly, modem point-feeder pre-baked plants need less electricity than the Soderberg plants they replace. And, thirdly, the production of primary aluminium is being shifted to regions in which the production of electricity is mainly based on hydropower.