Book excerpt: This book sets out the current state of knowledge about what works in reducing impairments to children’s health and development. Little and Maughan’s book applies a high standard of proof and reproduces only the work of the leading intervention scientists from around the world. After discussing the real world challenges to more effective children’s services, the book goes on to cover policy and practice proven to change the lives of all children, and extends also to effective programmes targeted at children with specific disorders. Examples include changes in household income, early years support, moving families to less disadvantaged communities, improving parenting and using schools to better mental health. The benefits of evidence-based programmes are specified, as are the costs to society of not intervening. The evidence is used to make recommendations about getting effective policy and practice into routine use, and includes illustrations of successful applications of these ideas.