Copper is, due to its divergent properties, a popular metal. Nevertheless, from the ecological point of view, processing of copper has some drawbacks. For example, copper ores contain elements, like sulphur, which could be damaging. Recently, global copper-demand increased, mainly due to rising Chinese imports. In the longer-term, the environmental impacts could intensify as an increase in demand for copper products is expected, so enforcing growing mining and processing activities. However, at least two trends can counteract these developments: technical progress and increased use of recycled metal. The objective of this study is to discuss whether the trends will enforce a sustainable development of the copper material flow, focusing on carbon-dioxide emissions and sulphur. The study is made by using a process-based partial equilibrium model, modelling the global copper material flow, considering recycling of copper as well as by-products. The allocation of output and technology to regions is based on economic decisions subject to the constraints set by existing techniques. By discussing the longer-run development of the global copper material flow, one scenario will be computed.