Peter K. SmithPeter K. Smith, PhD, is Professor of Psychology and Head of the Unit for School and Family Studies at Goldsmiths College, University of London. His research interests are in social development, play, bullying in school, and evolutionary theory. Dr. Smith is coauthor of Understanding Children's Development and coeditor of The Nature of School Bullying and the Blackwell Handbook of Childhood Social Development. He has written widely on children's play, particularly on pretend play training and rough-and-tumble play. Dr. Smith is also a Fellow of the British Psychological Society.