Research evidence on bully-victim problems has accumulated rapidly in recent years. From this, there is little doubt that prolonged involvement in bullying, as a perpetrator, victim, or, not uncommonly, as both a perpetrator and target of bullying, conveys risk for many aspects of development. As in many emerging areas of psychological science, diverse research efforts evolved more or less independently, producing a very large and rich body of knowledge, but making it difficult to gain a comprehensive, integrated view of the overall evidence base. Preventing and Treating Bullying and...