There is now little doubt that global warming is happening, that it is largely caused by carbon dioxide (CO2) emissions from human activity, that the effects on some communities will be devastating and that a substantial cut in emissions will be necessary to limit the damage. Politicians have woken up to the problem and have made ambitious commitments, but do they really know how these will be fulfilled? This briefing reviews the targets and commitments and the technology that could be used to meet them in the transport sector.