Up to now: Without cement, there is no concrete. However, the tried-and-tested binding agent for this mass building material has a high carbon footprint. Researchers at the Karlsruhe Institute of Technology (KIT) are working together with partners from four European countries on the EU-funded C-SINC project to develop a climate-friendly material that will partially replace cement. They are using CO2-bound magnesium silicates, which permanently trap carbon dioxide in mineral form. Concrete produced with this cement substitute not only causes significantly fewer emissions. It can actively store carbon and thus remove it from the atmosphere.