Abstract
This article begins with an overview of the policy environment in the United States and abroad for skilled immigration, with a particular focus on “supply-driven” versus “demand-driven” systems. The overview emphasizes that firms play a central role in the skilled immigration process in most countries. I then survey the ample evidence that skilled immigrants have a strong positive effect on firm outcomes, followed by a discussion of the many margins of adjustment that firms have when their access to skilled immigrants is affected by national immigration policy. Finally, given such margins of adjustment and the importance of skilled immigrants to firms, I consider how the policies that affect skilled migration shape the global geography and quality of innovation. I conclude by discussing policy implications and open questions. In particular, I emphasize that evaluations of the impact of skilled immigration should not be constrained within borders: immigration flows and national immigration policies affect the global geography of innovation and investment.