Olweus (1978) compared the self-esteem of pre-adolescent boys identified as bullies with that of boys who were identified as victims of others' teasing and harassment, and of a control group consisting of well-adjusted children. The clearest differences emerged between victims of harassment and the control children; victims had a lower self-esteem than controls. Bullies scored lower than the control children in one comparison, while in the other there was no such difference.