The aim of this thesis is to make an overview of the shortcomings of the ASEAN countries, China, Japan and South Korea for forming a monetary union. On the economic front, the degree of labor mobility, the interregional trade pattern, the trade composition, the degree of symmetry in economic development and external disturbances will be evaluated. Moreover, the monetary and fiscal performances of those countries will be evaluated on the basis of the Convergence criteria. Besides this, the stage of political and economic integration and the benefits of establishing a supranational institutional will be discussed.