Abstract

This article focuses on ageing populations, which are becoming more common around the world. The article also explores the possibility of cooperation among international cities as its research purpose. The cooperation among international cities is for the transfer of knowledge of adult guardianship system (hereunder “AGS”) law and AGS/supported decision-making (hereunder “SDM”) practices through the implementation of human resources training. Using fieldwork in Singapore and Tokyo including interviews with AGS/SDM experts and literature research, this article addresses potential collaboration in the areas of AGS/SDM among international cities to advance global concerns about ageing through exchanges that have not yet been formalized by any country or international/regional organization. A proposal is for Tokyo, Singapore, and Istanbul to form a joint project to implement AGS and SDM. Tokyo and Singapore could jointly cooperate with Bangkok, Jakarta, and Kuala Lumpur on the topic of AGS/SDM, and Tokyo and Istanbul could similarly collaborate with Bagdad, Baku, and Cairo. Cooperation among international cities could lead to friendships to assist one another on common social issues shared by cities and could encourage shared universal values of human rights without large budgetary expenditures.