This paper presents the methods and preliminary findings from IMPALA, a database that systematically measures the character and stringency of immigration policies. Based on a selection of data for six pilot countries between 1990 and 2008, we document the variation of immigration policies across...

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...

Migration decisions affect those left-behind in ways that are partly taken into account by market forces (e.g., wage effects on labour markets) and for the most part these can be seen as pure externalities. Diasporas are an example of such an externality. This paper reviews the recent economic...