This study examines the relationship between age and the injury outcomes for belted drivers in road vehicle crashes in the United Kingdom. The sample of 1,541 drivers was divided into three age groups: 889 drivers were aged 17–39 years (young drivers); 515 were 40–64 years (middle-aged), and 137 aged 65–84 years (older drivers). Both frontal and side impact crashes in which the vehicles sustained sufficient damage to be towed away from the scene are considered. In-depth information obtained from examinations of the crashed vehicles was combined with clinical data obtained from hospitals to throw light on the mechanisms that led to the injuries. Results show that in crashes of approximately equal severity, older drivers were significantly more likely than middle-aged and young drivers to be fatally injured in both frontal (p<0.001) and side (p<0.05) impact crashes. The results also show that older drivers sustained more injuries to the chest (p<0.0001) and that this body region is particularly problematic. The main sources of the chest injuries were found to be the seat belt in frontal crashes and the door in side impact crashes. As the number of older car users will increase rapidly in most OECD countries in the coming decades, the results suggest that vehicle re-designs are required, including in-vehicle crashworthiness systems, to take into account older people's relatively low tolerance of crash impacts.