To achieve goals for climate and economic growth, “negative emissions technologies” (NETs) that remove and sequester CO2 from the air will need to play a significant role in mitigating climate change. Unlike carbon capture/storage technologies that remove CO2 emissions directly from large point sources e.g. coal power plants, NETs remove CO2 directly from the atmosphere or enhance natural carbon sinks. Storing the CO2 from NETs has the same impact on the atmosphere and climate as simultaneously preventing an equal amount of CO2 from being emitted, and may be less expensive than direct emission reduction from fossil fuel burning. Many ideas for carbon removal are now being progressed.