The Okayama Education for Sustainable Development (ESD) Project is an ongoing initiative in Okayama City, Japan, established in 2005 by the Regional Centre of Expertise (RCE) Okayama and the Okayama Municipal Government with the aim "to create a community where people learn, think and act together towards realising a sustainable society". With a diverse participant base of over 240 organisations--including community learning centres ("kominkans"), schools, universities and non-governmental organisations (NGOs)--this initiative has administered numerous programmes. It has engaged a large and diverse group of citizens from Okayama City in exploring sustainability issues through collective discussion, envisioning and practice with the aim of living more sustainable lives. The decade-long experience of the Okayama ESD Project has gained international attention, and the "Okayama Model" is considered an inspiring example of community-based ESD due to the positive changes it has supported. In this article, the Okayama ESD Project is presented as a case study on effective social learning for sustainability. In particular, the practical efforts made are examined to provide insights into how various elements of a social learning process were strengthened and linked to create active learning cycles among community members. In addition, the conditions for creating an effective "learning community" are investigated, while the practical actions taken are examined in relation to creating an effective "social learning process." Finally, this article presents the important role which social learning has played in Okayama City's transition to sustainability and identifies the key efforts made to address and link each of these elements of social learning into a dynamic cycle.