As a region, the ten nations of ASEAN emitted 1.65 Gtpa CO2 in 2020 from the combustion of fossil fuels. Analyses reveal that ASEAN’s renewable energy resources are low to moderate and unevenly distributed geographically. Furthermore, there are substantial sustainable issues related to hydropower and bioenergy. The current rate of addition of new renewable power capacity is too slow to allow ASEAN countries to achieve net-zero by the middle of the century. More tools, in addition to renewable energies, will be needed. It is found, however, that carbon capture and storage (CCS) is a key enabling technology to decarbonize ASEAN’s fossil-fuel power and industrial plants and to produce blue hydrogen needed to decarbonize the industry sector. Furthermore, results of CO2 source-sink mapping exercises show that there is enough capacity in major sedimentary basins in ASEAN to permanently store two centuries of anthropogenic CO2 emission. Six first mover large-scale CCS projects in ASEAN with potential to mitigate up to 300 Mtpa CO2 from Singapore, Indonesia, Malaysia and Thailand have been identified. Furthermore, the steps needed to implement these CCS projects are also discussed.