This is the first book that covers comprehensively the difficult ethical issues involved in prevention of intellectual disability (learning disability, mental retardation). These issues are discussed both practically and theoretically in the light of four case examples drawn from real life. The cases demonstrate various issues raised by the concept of preventing intellectual disability, including definition, epidemiology, screening, and genetic counselling. Two major approach models (reproductive autonomy and public health) are scrutinised, and the practical issues of prevention are examined closely with respect to three syndromes (Down, Fragile X, and Aspartylugosaminuria). The question 'Why should intellectual disability be prevented?' is examined thoroughly at each stage. As a paediatrician and a philosopher, Dr Louhiala presents the issues in a way that is both user-friendly and philosophically sound.