Sir Roderick Floud is Provost of Gresham College, London. He is editor of The Cambridge Economic History of Modern Britain (Cambridge University Press, 2004) and has published many books on British economic history including Height, Health and History: Nutritional Status in the United Kingdom, 1750–1980 (with Kenneth Wachter and Annabel Gregory, Cambridge University Press, 1990). He is a Research Associate for the National Bureau for Economic Research, and has received a knighthood for services to higher education. Robert William Fogel is a Professor of Economics and the Charles R. Walgreen Distinguished Service Professor of American Institutions at the University of Chicago Booth School of Business, where he is Director of the Center for Population Economics. His many published titles include The Escape from Hunger and Premature Death, 1700–2100: Europe, America, and the Third World (Cambridge University Press, 2004). He is a Research Associate for the National Bureau for Economic Research, and received the Nobel Prize in economics in 1993. Bernard Harris is Professor of the History of Social Policy at the University of Strathclyde. His published titles include The Health of the Schoolchild: A History of the School Medical Service in England and Wales (1995) and The Origins of the British Welfare State: State, Society and Welfare in Britain, 1800–1945 (2004). Sok Chul Hong is Assistant Professor of Economics at Sogang University, South Korea. His current research focuses on the medical and environmental technological innovation of human development.