Anthropogenic climate change is mainly caused by aerosol emissions and greenhouse gases, of which CO2 has the greatest influence. Combustion engines, coal- and gas-fired power plants and industrial processes have caused an increase in atmospheric CO2 concentration from 280 ppm (pre-industrial) to a record concentration of 421 ppm in May 2022. Climate warming is accompanied by changing precipitation patterns, severe weather events and less weather predictability. This poses a major challenge for plant production and thus for food security and the preservation of biodiversity. Within the framework of ACCeSS, Heinrich Heine University Düsseldorf (HHU), Forschungszentrum Jülich (FZJ) and RWTH Aachen (RWTH) are combining their strengths and expertise in green and white biotechnology as well as membrane biology to tackle this major challenge of the 21st century. ACCeSS represents a circular approach to deliver solutions and new concepts that make man-made CO2 manageable. It will use energy to fix CO2 by photosynthesis into carbohydrates, which will then be converted into high-value or bulk compounds by chemo-/biocatalysis. ACCeSS will thus help to create the foundations for interdisciplinary methods/technologies for climate-neutral to net CO2-negative processes.