The building of an East Asian community is now on the agenda of policy makers but rivalry among regional powers (Japan, China, South Korea) as well as discord within ASEAN seemingly hinder further progress. How can momentum for regional community building in East Asia be obtained? How can ASEAN recover the initiative in that process? This project is based on the premise that the question of region-wide gaps (especially “ASEAN divide”) and how to deal with it holds a key for the future of regional integration in Asia. From this vantage point of seeking policy relevant findings, this project seeks to ascertain whether and in what way a common effort to solve regional development gaps could contribute to regional institution building, especially with regard to Asia, through policy-focused comparative case studies of the role of regional developmental effort in Europe (EU) and South America (MERCOSUR). European integration was said to be facilitated by relatively high and close level of GDP per capita of its member countries (except Southern Italy and Southwest France). However, each phase of enlargement compounded imbalances. The EU initiated regional policy to consciously reduce regional income disparities of its members and put in place pre-accession cooperation policy for candidate countries. MERCOSUR, founded in 1991 with Argentina, Brazil, Uruguay, and Paraguay, is widely seen as the most advanced regional institution after the EU. MERCOSUR has started “MERCOSUR social” with Ministerial Council and Permanent Secretariat since 2001 and is equipped with Structural Convergence Funds. There are some regional reorganization moves around MERCOSUR (especially UNASUR) and the question of income disparity plays an important role. This project employs comparative case studies method to analyze 1) the timing of introduction of policy, 2) the process of policy making, and 3) the content of policy, in view of evaluating whether each of the three aspects of policy contributed to 1) political support for regionalism, 2) capacity building of the regional institution, and 3) raising of regional identity of citizens. Decision-making analysis using interviews and primary sources will be employed along with focused analysis of data including economic income statistics and regional public opinion surveys (Eurobarometer and Latinobarometer). Research for this project will be undertaken at the following two sites. For research on Europe, the Institute of Political Studies of the University of Bordeaux is chosen. It houses an important research center on International Relations with renowned specialists on comparative regionalism especially on the EU, and on territorial politics including the role of the EU therein. As far as research on South America is concerned, the regional bank, the Inter-American Development Bank, is ideally suited to pursue empirical analysis on South America. 　Existing studies on EU’s regional policy suggest that although economic effects of such measures are still debated, its political role in gaining political support for furthering regionalism is established. The comparative case studies will systematically analyze political aspects of regional development policy, and are expected to yield policy relevant conclusions for Asia in the form of a book or journal articles.