Dr Yasuhiko is a Professor at the University Research Center and Adjunct Professor at the School of Medicine at Nihon University, Tokyo, Japan. He has served as a council member of the International Union for the Scientific Study of Population (IUSSP) from 2005 to 2009 and has been serving as an executive committee member of the International Social Science Council (ISSC) representing IUSSP since 2010. He obtained his Ph.D. (Sociology) from the University of Southern California, Los Angeles, USA. His specializations are in demography and gerontology, and he has been working on population aging and health issues in both developed and developing countries. He promotes data collection for the study of aging and health in Asian countries. Over the last 15 years, he has conducted a six-wave national longitudinal survey on aging and health in Japan.