Cancer is the second commonest cause of death, after accidents, among children in developed countries, while in developing countries, improvements in the control of communicable diseases and the occurrence of premature delivery may lead to the emergence of cancer in children as a greater public health problem than in the past. The rationale for considering childhood cancers separately from cancers in adults in that there are differences in the sites of occurrence, in the histological appearance and in their clinical behavior. This book reviews the epidemiology of specific types of childhood cancer to mid-1997. The scale of the problem is first reviewed in a major compilation of data on the descriptive epidemiology of childhood cancer, then separate chapters describe studies of the different postulated causal factors and summarize what can be concluded from them.