Editor’s Note: Along with the process of urbanization, the regionalization of urban development is becoming a popular phenomenon all over the world in the contemporary time. It has resulted in the emerging and growth of urban agglomerations, and city clusters as well, which are very often combinations of multiple local territories of different levels. This phenomenon is represented socially by the daily cross-border mobility of people for various purposes, economically by the frequent cross-border interaction of industrial clusters, and physically by the seamless cross-border continuity of built up areas. While the agglomeration of industrial clusters underpins both the social and economic flows at the regional level, the transportation systems and the internet technologies are obviously the two types of infrastructure that support the emerging and growth of urban agglomerations and city clusters, in physical and virtual forms respectively, to meet the demands of industrial cluster development. In consequence, the regions concerned are transformed into a kind of network society, as described by Manuel Castells in his groundbreaking trilogy, The Rise of Network Society. This development trend also took place in China amid its accelerating process of urbanization in the past four decades, with its significance calling the attention of the national policy-makers at the turn of the new century. In 2006, it was proposed in the 11th Five-Year Plan for the first time to take city cluster as the main spatial form of urbanization, making the development of city clusters become a national strategy of China to promote regional coordination and to optimize the spatial form of urbanization. However, in spite of the implementation of this national strategy until today, the development of city clusters has always been facing the challenge of regional coordination, especially in term of spatial development. The lack of cross-border coordination mechanism of the existing spatial planning system often leads to the possibilities of conflict among neighboring local territories when they implement ecological, agricultural, and urban zoning, locate Not-In-My-Back-Yard facilities, realize regional infrastructure project, and so on. This shall be a task of spatial planning system reform, with regard to which, the regional coordination mechanism of industrial cluster development following market principles may imply a useful reference.