This book aims to provide a new perspective on the study of transnationality. In this Introduction and in related work (Crang et al. 2003), we argue that most current work in this rapidly expanding ﬁeld has underestimated the signiﬁcance of space in the constitution of various forms of transnationality. Previous studies have emphasized the importance of transnational corporations and business networks (Dicken 1986; Yeung 1998; Beaverstock and Boardwell 2000). They have examined the scope of transnational urban politics and social movements (Smith and Guarnizo 1998; Smith 2001) and explored the signiﬁcance of newly emerging transnational cultural forms (Appadurai 1986, 1996; Hannerz 1996). But, in our collective view, such studies of the economic, political and cultural dimensions of transnationalism have characteristically under-played the transformation of space that is involved in the evolution of transnational social forms. Rather than taking space as a passive backdrop to transnational social relations, we argue that space is constitutive of transnationality in all its different forms.