Iron deficiency in infancy is very widespread, even in developed countries and even when there is no general malnutrition. This book examines the question whether iron deficiency in early life leads to deleterious changes in brain and/or behavioural development. Each of the nine contributors comments critically on each of the other eight chapters, so that the book is very extensively peer-reviewed. The evidence is set out so that the reader may make his own informed judgement. Iron deficiency could very easily be prevented; this fact is of prime importance if such deficiency has long-lasting effects on human intellectual capacity and achievement.