Miles Hewstone is Professor of Social Psychology at the University of Oxford. His current work centres on the reduction of intergroup conflict via intergroup contact, stereotype change, and crossed categorization. Professor Hewstone is a former editor of the British Journal of Social Psychology and co-founding editor of the European Review of Social Psychology. He has also been the recipient of numerous prizes including the Spearman Medal (1987) and the Presidents' Award for Distinguished Contributions to Psychological Knowledge (2001), from the British Psychological Society. He has authored and edited several books, including Psychology (2005, Blackwell) and Minority Influence and Innovation (2010, Taylor and Francis). Wolfgang Stroebe has taught social psychology at universities in the USA, UK, Germany and The Netherlands and is now Professor at Utrecht University and the University of Groningen, both in the Netherlands. He is editor with Miles Hewstone of the European Review of Social Psychology. He has authored and co-authored eight books and more than a hundred scientific articles and chapters on topics of social and health psychology. He is Fellow of a great number of international associations and has received numerous awards for his scientific work. Klaus Jonas has taught social and organizational psychology at universities in Germany, Austria and Switzerland. He is Professor of Social and Business Psychology at the University of Zurich. He has published on attitudes, stereotypes and human resource management. His current interests concern the influence of leadership on performance and satisfaction of subordinates.