Many studies have shown that psychophysiological parameters of processing emotional stimuli are associated with different personality traits in children, adolescents, and adults. Individuals with low autonomic baseline arousal, low orienting reaction, accelerated habituation, and reduced excitability particularly to punishing stimuli are characterised by a reduced experience of anxiety, decreased behaviour inhibition, and increased sensation seeking. These characteristics seem to raise the likelihood of dis-social behavior and are perceived as prognostically favourable for the development of antisocial personality disorders in childhood and adolescence. In contrast, an increased disposition towards anxiety, which is associated with increased autonomic reactivity, is recognised as a protective factor. Current data have shown that through special training, child and adolescent autonomic reactivity could be enhanced. Due to its versatility, this biological marker might be used for prevention in children at greater risk of developing antisocial behaviour.