Cement manufacturing produces 5.6% of global CO2 emissions. This research finds that capturing 80% of cement’s process emissions (and no thermal emissions) by 2050 can make cement carbon-neutral, as natural carbonation offsets remaining emissions. If thermal fuel supply were fully decarbonized by 2050, a 53% process emissions capture rate achieves carbon-neutral cement. Higher capture rates than these would provide net negative CO2 emissions and the possibility that simply making concrete could reduce atmospheric CO2 concentrations.