Tara Callaghan (Ph.D., Psychology, 1982, Brown University) teaches at St.Francis Xavier University (St. FXU), Nova Scotia, Canada. Her current research interests include symbolic development, pictorial understanding, and the role of culture in early social cognition. She founded the Centre for Research in Culture and Human Development at St. Francis Xavier University and in the past decade has established field research sites in several countries around the world.Henrike Moll (Ph.D., Psychology, 2006, University of Leipzig) is a postdoctoral researcher (Dilthey Fellow) in the Psychology Department of the Max Planck Institute for Evolutionary Anthropology. She studies early social cognition with an emphasis on joint attention and perspective taking.Hannes Rakoczy (Ph.D., Psychology, 2004, University of Leipzig) is Professor in the Department of Psychology and Research Fellow in the Courant Research Centre for Evolution of Social Behavior at the University of Gottingen, Germany. His research interests include theory of mind, development of shared intentionality and normativity, and the development of play.Felix Warneken (Ph.D., Psychology, 2007, University of Leipzig) is Assistant Professor in the Department of Psychology at Harvard University. His research interests are altruism and cooperation, social cognition in young children and great apes, and children’s understanding of normativity.Ulf Liszkowski (Ph.D., Psychology, 2005, University of Leipzig) is leader of the Max Planck Research Group Communication Before Language at the Max Planck Institute for Psycholinguistics in Nijmegen. His research focuses on infants' gestural communication, the role of prelinguistic infants' social-interactional input across different cultures, infants’ understanding of mental states, and infants’ expectations of and motivation for joint collaborative acting.

• I. INTRODUCTION II. GENERAL METHODOLOGYIII. INDIVIDUAL STUDIESIV. GENERAL DISCUSSIONREFERENCESACKNOWLEDGMENTSCONTRIBUTORSSTATEMENT OF EDITORIAL POLICYSUBJECT INDEX