Brian D. Loader is Associate-Director of the Science and Technology Studies Unit (SATSU) based at the University of York, UK. His academic interests are focussed around the emergence of new information and communications technologies (ICTs), such as the Internet, and the social, political and economic factors shaping their development and diffusion, and their implications for social, economic, governmental and cultural change. He is General Editor of the international journal Information, Communication and Society and has published extensively in this field. Recent books include Cyberprotest:New Media, Citizens and Social Movements, (Routledge, 2004); Young Citizens in the Digital Age (Routledge, 2007); Digital Welfare for the Third Age (Routledge, 2008). Ariadne Vromen is Associate Professor in the Department of Government and International Relations at the University of Sydney, in Australia. She has ongoing research interests in political participation, including on young people, politics and the internet. Michael Xenos is Associate Professor of Communication Science at the University of Wisconsin-Madison, USA. His research focuses on how the context and content of political communication influences the quality of democratic deliberation, public opinion, and civic engagement. He is particularly interested in how different aspects of political information environments affect processes of opinion formation and civic engagement. Some of his recent projects have explored how factors such as campaign intensity, negative campaigning, new communication technologies, and new sources of political information like late-night comedy and youth political websites, enable or constrain democratic citizenship.