Michael Tomasello (Ph.D., 1980, Psychology, University of Georgia) taught at Emory University and worked at Yerkes Primate Center from 1980 to 1998. Since 1998, he is Co-Director at the Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany. Research interests focus on processes of social cognition, social learning, and communication and language in human children and great apes. Books include Primate Cognition (w/J. Call, Oxford University Press, 1997), The Cultural Origins of Human Cognition (Harvard University Press, 1999), and Constructing a Language: A Usage-Based Theory of Language Acquisition (Harvard University Press, 2003). Malinda Carpenter (Ph.D., 1995, Psychology, Emory University) currentlyis a member of the scientific staff of the Department of Developmental andComparative Psychology at the Max Planck Institute for Evolutionary Anthropology.Her research interests include imitation and other types ofsocial learning, infants’ understanding of intentions and other mental states,and joint attention and other early social-cognitive skills. She has workedwith typically developing infants and young children, young children withautism, and apes. R. Peter Hobson (Ph.D., 1989, FRCPsych, CPsychol) is Tavistock Professorof Developmental Psychopathology in the University of London. He is anexperimental psychologist and psychiatrist (and psychoanalyst), trained atCambridge University and the Maudsley Hospital, London, and now at theTavistock Clinic, London and the Institute of Child Health, University College,London. His primary research interest is the contribution of socialrelations to early cognitive as well as social development. His principal fieldsof study are early childhood autism, congenital blindness, mother–infantrelations, and adult borderline personality disorder. His first book wasentitled Autism and the development of mind (Erlbaum, 1993), and his secondmore accessible and wide-ranging book is called The Cradle of Thought(Oxford University Press, 2004).

• Abstract vii. I. Introduction 1.II. The Emergence of Social Cognition: A Longitudinal Study 29.III. Understanding Intentional Action 46.IV. Understanding Perception and Attention 73.V. Joint Intentions and Attention 92.VI. General Discussion 107.References 123.Acknowledgements 132.Commentary- Social Engagement and Understanding in Chimpanzees and Humans.R. Peter Hobson 133.Contributors 153.Statement of Editorial Policy 154