The CO2 Human Emissions (CHE) project will coordinate efforts towards developing a European monitoring capacity for anthropogenic CO2 emissions. This challenging target is aligned with the European Commission’s stepwise approach for a requirement-driven integration of Earth observations, from remote sensing and in situ, with enhanced modelling capabilities for CO2 fossil fuel emissions, along with other natural and anthropogenic CO2 emissions and transport. The project will pursue a consolidated methodology for integrating the monitoring system components, as well as innovation for estimating fossil fuel CO2 fluxes. These include reconciling bottom-up and top-down constraints and handling systematic errors of satellite sensors. Earth observations from satellites will be combined with in situ CO2 observations and information from co-emitters or isotopes to support the attribution of fossil fuel emissions and uncertainty reduction. Methodological advances will include a representation of anthropogenic CO2 variability in space and time, responding to documented shortcomings and needs, and a carbon cycle data assimilation system extended to enable estimates of emission uncertainties. Strategies to separate anthropogenic CO2 emissions from biogenic fluxes at country to global scales using observations and models will be documented. CHE will support a large community by providing a library of realistic CO2 simulations from global to city scale to examine the capacity for monitoring future fossil fuel emissions and to adequately dimension space mission requirements. Community building will include direct collaboration across 22 European institutions, and communication and liaison with key European and international stakeholders. These coordination efforts will ensure the transfer of science and technology requirements and recommendations for strengthening existing assets with a view to developing an anthropogenic CO2 monitoring service.