An influential strand of research has tested for the effects of immigration on natives' wages and employment using exogenous refugee supply shocks as natural experiments. Several studies have reached conflicting conclusions about the effects of noted refugee waves such as the Mariel Boatlift in...

In response to the recent migrant and refugee crisis, rich countries have redoubled policy efforts to deter future immigration from poor countries by addressing the "root causes" of migration. We review existing evidence on the effectiveness of such efforts. First, aid disbursements do not...