During the course of its efforts to host the 2012 EXPO in Yeosu, Korea, the Korean government promised to the members of the International Exhibition Bureau (BIE) to adopt the so-called Yeosu Declaration. Considering the year 2012 will likely witness the adoption of another global scale environmental declaration as such as the Stockholm, Rio and Johannesburg Declarations, Yeosu Declaration may contribute not only to emphasizing the theme of the 2012 Yeosu EXPO, The Living Ocean and Coast: Diversity of Resources and Sustainable Activities, but also to sharing its efforts to protect the environment with the international society. As there has been no precedence of adopting any declaration in the history of EXPO, a careful preparation for the adoption of Yeosu Declaration is necessary as suggested in this article.