Driving takes place in a social environment where other road users have a strong influence on driving behaviour. One aspect of this social situation is interpersonal interaction which can lead to emotional responses in some cases. One of the most frequently emerging emotions in driving is that of anger (Nesbit et al., 2007) and the most common response to anger is aggressive behaviour. From the psychological point of view aggressive behaviour has a functional purpose. Aggressive behaviour is intended to restore the original unrestricted situation to allow free driving (Kaba et al., 1997, Shinar 1998, Neighbors et al., 2002). Aggressive driving, and in its extreme, road rage, are characterised by speeding, risky driving, and dangerous manoeuvres motivated by self-interest. Aggressive driving can be seen as a substantial contributor to traffic incidences. To understand the role of aggressive driving and its relationship with motor vehicle accidents, a survey was carried out by the American Automobile Association Foundation for Traffic Safety (2009). The results show that between 2003 and 2007 about 56 per cent of all motor vehicle accidents included at least one aggressive action of one of the participants. Thus emotions – especially anger – and their behavioural consequences play an important role in safe driving.