Although scientists are highly internationally mobile, it is not always clear if mobility is beneficial, and if so, in what circumstances. Our GlobSci project, which surveyed 17,852 scientists working in 16 countries (1), allowed us to examine outcomes related to mobility across a wide array of countries, rather than focus on mobility to the United States, as many studies do. We find that the impact factor of research by foreign-born scientists (measured by country of residence at age 18) is on average higher than that of natives who have no international mobility experience. The effect persists when we account for the fact that migrant scientists may be selected from among the best in the origin country, using individual-level data on migration during childhood, which is correlated to the likelihood of subsequent international mobility but arguably not correlated to the scientific quality of the migrant. Our findings suggest that cross-border mobility comes with a boost in research quality that would have been absent without mobility (2). The boost is consistent with the theory that migration enhances performance by facilitating knowledge recombination and specialty matching. In other work, we examined the role that mobile scientists play in the performance of single-laboratory–based research teams. Studying 4336 teams from among the 16 countries, we find a performance premium (in terms of impact factor and 3and 6-year citation counts) for teams with a foreign-born corresponding author. This premium persists when comparing labs within a country and within the same institution. The premium is larger when migrants occupy a position of decision power in the team, such as the principal investigator, when the paper is reported by the respondent to be highly creative, and when the team works in an area of science where knowledge is produced predominantly in a few geographic locations (3).