This book explores how Olweus developed the first widely used questionnaire to survey the issue of bullying and victimisation (the Olweus Bullying Questionnaire, or OBQ), was instrumental in designing the first intervention campaign against school bullying in Norway in the 1980s and developed a multi-layered program of intervention, the Olweus Bullying Prevention Program (OBPP), which is used in many countries around the world.