PUBLI : Hein de Haas, Mathias Czaika, Marie-Laurence Flahaux, Edo Mahendra, Katharina Natter, Simona Vezzoli, Maria Villares-Vilera, « International Migration : Trends, Determinants, and Policy Effects, Population and development review, 2019


This paper synthe­sizes insights from new global data on the effec­ti­ve­ness of migra­tion poli­cies. It inves­ti­gates the complex links between migra­tion poli­cies and migra­tion trends to disen­tangle policy effects from struc­tural migra­tion deter­mi­nants. The analysis chal­lenges two central assump­tions under­pin­ning the popular idea that migra­tion restric­tions have failed to curb migra­tion. First, post-​WWII global migra­tion levels have not acce­le­rated, but remained rela­ti­vely stable while most shifts in migra­tion patterns have been direc­tional. Second, post-​WWII migra­tion poli­cies have gene­rally libe­ra­lized despite poli­tical rhetoric sugges­ting the contrary. While migra­tion poli­cies are gene­rally effec­tive, “substi­tu­tion effects” can limit their effec­ti­ve­ness, or even make them coun­ter­pro­duc­tive, by geogra­phi­cally diver­ting migra­tion, inter­rup­ting circu­la­tion, encou­ra­ging unau­tho­rized migra­tion, or promp­ting “now or never” migra­tion surges. These effects expose funda­mental policy dilemmas and high­light the impor­tance of unders­tan­ding the economic, social, and poli­tical trends that shape migra­tion in some­times coun­te­rin­tui­tive, but powerful, ways that largely lie beyond the reach of migra­tion policies.

Publi­shed online