This paper points out and examines some tasks used to introduce a social impact bond to solve social difficulties, and explains a social impact bond project which is now under consideration for implementation in the Kansai area. In Japan's society characterized by a declining population, a social impact bond is an attractive financial scheme to give incentive for cutting costs of various utilities, but multiple underlying problems present themselves when such a scheme is put into practice. If this social bond project is actually realized in Kansai, it will be a pioneer case for Japan. Its success or failure will be closely watched.