Transnationalism in a Comparative Perspective: An Introduction Godfried Engbersen, Linda Bakker, Marta Bivand Erdal & Özge Bilgili CMS ２ (３): ２５５–２６０ DOI: １０.５１１７/CMS２０１４.３.ENGB Since the publication of ‘Nations Unbound’ (Basch et al. 1994), studies on transnationalism have mushroomed. Despite ongoing debates about the nature of the concept, and the newness of the phenomenon, there is a growing consensus about the importance of taking into account migrants’ multi-stranded social ties which link together societies of origin and sett- lement. There is also a strong push to move away from ‘methodological nationalism’ in order to better understand the manifold ties, identifica- tions and activities of migrants and non-migrants across international bor- ders (Wimmer & Glick Schiller 2002; Vertovec 2009). The first generation of transnational studies focused strongly on trans- national practices, such as economic transnationalism (including remit- tances), political transnationalism (social movements, diaspora politics), and identity formation, social remittances and ethnic entrepreneurship (see e.g. Guarnizo et al. 2003; Khagram & Levitt 2008). While many of these studies were based in the immigration-receiving context of the Uni- ted States (see e.g. Portes et al. 1999; Itzighsohn and Saucedo 2002; Wal- dinger and Fitzgerald 2004), soon after transnationalism theory was also incorporated into European migration studies (Snel et al. 2006; De Haas & Fokkema 2011; Erdal & Oeppen 2013). The European context offers highly relevant research sites for transnational studies, mainly because many of the EU countries today can be considered immigration countries with considerably large permanent migrant groups and continuous inflows that create new connections with diverse countries of origin. In relation to this, it is important to mention that the European Union (EU) 2004 and 2007 enlargements created a borderless zone that boosted existing trans- national patterns within the EU and generated complex new ones. More- over, European welfare states offer particular structural conditions for both 255 ENGBERSEN