Introduction: East Asia's De Facto Economic Integration; M.Fouquin, D.Hiratsuka & F.Kimura The Development of Fragmentation in East Asia and Its Implications for FTAs; F.Kimura Intra-Industry Trade and Economic Integration; P.Ecochard, L.Fontagné, G.Gaulier & S.Zignago Production Networks and Spatial Linkages in East Asia; I.Kuroiwa Catching Up of Manufacturing Cum De Facto Economic Integration in East Asia; D.Hiratsuka China's Specialization in East Asian Production Sharing; G.Gaulier, F.Lemoine & D.Ünal-Kesenci Vertical Intra-Regional Production Networks in East Asia: A Case Study of the Hard Disc Drive Industry; D.Hiratsuka A Comparison of De Jure Economic Integration in East Asia: Is East Asia Discriminating Against Itself?; M.Freudenberg & T.Paulmier Regionalization in East Asia: Simulations Using a CGE Model MIRAGE; M.Fouquin