Matthias Koch, Ph.D. (1997), is Senior Researcher in Social and Economic History at the German Institute for Japanese Studies, Tokyo. He has published widely in the area of Japanese Studies and is currently writing a book on the population history of Japan.Claus Harmer is system administrator at the German Institute for Japanese Studies, Tokyo. He has developed and programmed several databanks and virtual exhibitions containing social scientific research data.Florian Coulmas, Ph.D. (1978), is Director of the German Institute for Japanese Studies, Tokyo. He has compiled two dictionaries and published widely about Japanese society and culture. He is one of the editors of The Demographic Challenge: A Handbook about Japan (forthcoming).