The transport sector is the largest and fastest growing consumer of energy in Europe, which poses a serious threat to Europe’s climate and environment. Over recent decades, increases in passenger and freight transport movements have both been responsible for this growth. These trends can be observed in most European countries including the Netherlands and the United Kingdom (UK), where per capita transport fuel consumption increased by 9% and 4% respectively in the relatively short period between 2000 and 2006 (and by 37% and 16% respectively between 1990 and 2006). In many ways, general travel patterns in these two countries have not changed substantially during this period: total travel distance, average travel speed and travel time have all remained fairly constant. What has changed, however, is car occupancy, the type and age of vehicles on the road and the average number of trips, all of which have contributed to changes in energy consumption in the passenger transport sector. In this paper we focus on trends in individual mobility and related carbon dioxide (CO2) emissions, which are a close proxy for fuel consumption and total greenhouse gas (GHG) emissions from transport. National travel data for the Netherlands and the UK from 2000 onwards are used to examine these trends. We construct a classification of individuals based on their travel patterns and related CO2 emissions with the aim of identifying the key socio-economic characteristics of individuals with high and low CO2 emissions. We then examine the extent to which these socio-economic characteristics are similar in both countries. Preliminary analyses reveal that in both countries around 10% of the population is responsible for almost half of all CO2 emissions in the passenger transport sector. At the other end of the spectrum, half the population is responsible for only 10-20% of passenger transportrelated CO2 emissions. Substantial differences in individual transport CO2 emissions are apparent according to socio-economic characteristics such as age, gender, income and employment status.