He received his PhD in Area Studies from Kyoto University and is a co-editor of several books, including Global Studies from People’s Perspectives: In Search of Philosophy and Practice of Co-existence (2016, Sophia University Press, written in Japanese) and A Social History of Development: Dynamics of Gender, Minority and Periphery in Southeast Asia, (2010, Fukyosha, written in Japanese). His current research concerns the ethnogenesis and Islamization of the “sea people”, the Bajau in particular, in insular Southeast Asia. Since 1995, he has conducted fieldwork in more than fifty Bajau villages in southern Philippines, Sabah, Malaysia and eastern Indonesia.