Abstract
Different kinds of aggression are described, as well as how they are caused. The reactive aggression in which someone acts aggressively on the stimuli of the environment, is described in more detail. The reactive aggression is a combination of different acquired behaviour and is mainly aimed at the weaker ones. Aggression signals which cause this aggression can vary. It can be a policeman or a ticket-inspector in uniform. Aggression is becoming more and more evident, but something can prevent it. Examples of aggression in public transport are discussed. An effective anti-aggression policy is the prevention of aggressive behaviour.