Transport sector policies already contribute to moderating greenhouse gas emissions from road vehicles and are increasingly designed to contribute to overall societal targets to mitigate climate change. The Round Table investigated the effectiveness and costs of various mitigation options. The question of how to decide on the distribution of abatement efforts across sectors of the economy was also discussed. Within the broad topic of addressing greenhouse gas emissions from transport, the Round Table focused on emissions of CO2 from road transport and in particular from light-duty passenger vehicles. Policies that reduce fuel consumption below non-intervention levels are in place in most countries, many adopted for reasons other than reducing CO2 emissions. In the US, both fuel taxes and fuel economy regulations have been in force for some decades. European governments have adopted high fuel taxes but are now considering introducing fuel economy regulations. A first core question for the Round Table was whether such a combination of instruments is justified. A second question was whether current policies, and the level of taxes and standards, are in line with societal climate change mitigation goals and, more generally, how such goals ought to be defined.