Why do parents hit those they love? What effect does it have on children? What can be done to end this pattern? These are some of the questions explored in The Primordial Violence. Featuring longitudinal data from over 7,000 U.S. families as well as results from a 32 nation study, the book presents the latest research on the extent to which spanking is used in different cultures and the subsequent effects of its use on children and on society. Evidence that shows the relationship between spanking and the subsequent slowing of cognitive development and increase in antisocial and criminal behavior is shown. Both cross-sectional and longitudinal studies are explored in an accessible fashion. An abundance of high quality research has produced findings that are highly consistent from study to study which show that spanking is a risk factor for aggressive behavior and other social and psychological problems. Because of these findings, the authors argue for policy changes and recommend a drastic reduction in the use of spanking. Policy and practical implications are explored in most chapters.