This book examines the dynamic processes by which communities establish distinct notions of 'home' and 'belonging'. Focusing on the agency of diasporic groups, rather than (forced or voluntary) dispersion and a continued longing for the country of origin, it analyses how a diaspora presence impacts relations between 'home' and host countries. Its central concern is the specific role that diasporas play in global cooperation, including cases without a successful outcome. Bridging the divide between diaspora studies and international relations, it will appeal to sociologists, scholars of migration, anthropologists and policy-makers.