This chapter 1 . proposes to look at the political activities of diasporas 2 and how these are constrained as well as enhanced by local and national as well as international factors. Building on the cases of several diaspora groups living in London (mainly Cypriot, Irish, and South Asian), it focuses on several major issues: first, relying on the political opportunity structures theoretical framework as discussed in the general introduction of this volume, it explores the issue of diaspora politics in the country of settlement: how is it organized? Are the political parties representing diasporas pure extensions of political parties in the home country? What kinds of mobilization processes are at play? Second, this chapter aims to assess whether diaspora politics reproduce the divisions found in the country of origin or if they develop around new cleavages and issues. In other words, are diaspora politics a genuine duplication of politics in the home country, or are processes of autonomization emerging? Third, by critically reviewing the existing literature, this chapter enquires whether diasporas indeed are the heralds of “long distance nationalism” that many authors describe, and assesses to what extent they experience processes of re-traditionalization and identity withdrawal.