Before one can tackle bullying in schools one must first be convinced of its harmfulness. Fortunately there is now a great deal of hard evidence regarding the physical and mental harm that continued bullying does to vulnerable children (see Does bullying really do children any harm ?). Questionnaires administered at a school can help to assess the extent of the harm. It is known also that children who continually engage in bullying at school are more likely than others to engage in criminal activities after leaving schools.