Silhouette of people with luggage walking in a row. Andrey_Popov/Shutterstock.com Globalization has facilitated physical mobility, enabling international migration to increase from 92 million in 1960 to 244 million in 2017. Traditionally, rising migration flows have been attributed to a lack of economic development in origin countries. Would-be migrants, the argument goes, decide to move primarily in search of higher wages and income abroad. A competing hypothesis on the migration-development relation The “migration transition hypothesis,” first set forth by Wilbur Zelinsky in his seminal paper on the subject (1971), provided a more nuanced picture. Out-migration (emigration) first increases with development in a country until a certain turning point, after which it gradually recedes. Several scholars found empirical evidence for this, using mainly cross-sectional data (De Haas, 2010; Clemens, 2014; Dao et al., 2018). This suggests that in low-income countries economic development leads to more people using their increased financial capacity to migrate abroad, potentially eroding the country’s human capital and thus hindering its ability to develop sustainably.