Abstract
This research shows how the introduction of a regional SNS by Yatsushiro municipal government in Japan has been transforming the activity system of regional public communication and thus facilitating endogenous and sustainable regional development since 2004. Using the activity theory as an analytical framework, it compares and analyzes the activity system of regional public communication mediated by a regional SNS with the one mediated by conventional media. Through the operation of the regional SNS, Yatsushiro municipal government has built a communication platform that promotes sharing of interests, information, and knowledge among diverse citizens.
