Intro -- Preface -- Acknowledgements -- Abbreviations -- Executive summary -- Overview -- Key findings -- Structural components -- Skill components -- What else is potentially promising? -- 1. Introduction -- 2. Online violence against children -- 2.1 Subcategories, types and dynamics -- 2.1.1 Online child sexual exploitation and abuse -- 2.1.2 Cyber-aggression and cyber-harassment -- 2.2 Three implications for prevention -- 3. Strategies to prevent online violence against children -- 3.1 Prevention education -- 3.2 Legislation -- 3.3 Law enforcement and regulation -- 3.4 Public awareness -- 3.5 Helplines and hotlines -- 3.6 Safer environments, technology-engineered solutions -- 3.7 Other strategies -- 4. A guide to the evidence -- 5. Evidence from effective prevention education programmes -- 5.1 Prevention education for violence against children -- 5.2 Core components of prevention education -- 5.3 Prevention education approaches needing more research -- 6. Evidence for effective online violence against children programmes -- 7. What currrent prevention education programs are actually saying and doing to address online violence against children -- 8. Effective messaging -- 9. Conclusion -- 10. References -- Annex 1: Methodology.