Child maltreatment can result in not only immediate physical and mental harm to children but also long-term consequences throughout their lives. Measurably reducing child maltreatment requires action from politicians, practitioners and the public. Internationally, some individuals and groups have pioneered programs to prevent child maltreatment, or been instrumental in changing strategies or policies to protect children's rights. Although scholarly papers capture many of these successes, they can omit key points on how to establish and sustain successful interventions. This handbook -- based on a series of interviews with the world's leading experts on preventing child maltreatment -- fills this gap by providing practical information to policy-makers, practitioners and others on implementing prevention programs.After outlining the wider political and cultural landscape needed to drive and sustain interventions, the handbook describes key principles for selecting and delivering programs, and important practical considerations, including resources and technical support. Experts contribute insights into important first steps, key questions to consider and ways to address common challenges and barriers to successful implementation. This handbook is intended to be used, alongside other resources developed by the WHO Regional Office for Europe, to implement the European child maltreatment prevention action plan.