Migration flows are shaped by a complex combination of self-selection and out-selection mechanisms. In this paper, the authors analyze how existing diasporas (the stock of people born in a country and living in another one) affect the size and human-capital structure of current migration flows....

This paper reviews the existing literature on the impact of migrants networks on the patterns of international migration. It covers the theoretical channels at stake in the global effect of the networks. It identifies the key issues, namely the impact on size, selection and concentration of the...

This paper sheds light on the apparent paradox, wherein populations adversely affected by climatic conditions fail to migrate as much as would otherwise be expected. Drawing on Hirschman's treatise on Exit, Voice and Loyalty, we develop a simple model, which highlights the theoretical case for a...