Thanks for this discussion, David and Daniel. Daniel, my personal starting point is that I would feel a grave harm had been done to me if government agents informed me that I was restricted to live only in the place (city, state, or country) where I was born, and that my choice of where to live had been forcibly taken from me. I think most people feel this way, which is why the UN Universal Declaration of Human Rights confers an unqualified right to emigration on all people, skilled or not. We should thus demand a high burden of proof from anyone who feels that this right should be curtailed by any government. Meeting this burden of proof requires answering a long list of questions that we don't now have good answers to. Does skilled emigration necessarily deplete the stock of skilled workers in the country of origin? Rigorous case studies of small countries with very high rates of skilled emigration have cast doubt on this idea (Pedro Vicente and Catia Batista on Cape Verde, forthcoming JDE, and my work with Satish Chand on Fiji, among others). Skilled emigration greatly increases the incentive to invest in skill acquisition, and the net effects are complex. If skilled emigration *does* necessarily deplete the stock of skilled workers, what is the magnitude of human capital externalities? This is extremely poorly understood. Acemoglu and Angrist have trouble detecting any substantial schooling externality in the U.S., and Lant Pritchett has shown that it's very difficult to detect in African data as well. The idea that economic progress results naturally from a group of educated people forced to interact with each other because they can't go anywhere else is one that I would describe as untested. There's better evidence for causation in the other direction: People invest in skill when it has high returns for other reasons including basic institutions of sound political and economic governance. Finally, even if skilled emigration does necessarily deplete the skill stock *and* there are large externalities -- both of which are intuitively plausible but the world seems much more complex than this -- there remains the question of who *owns* those externalities. It is not at all clear to me that people near whom I was born hold a property right in the positive externalities I may or may not convey to others. Why do other Indians hold more of a property right in the external effects of a smart Indian's talents than the Indian herself does? If they own those positive external effects, do other Indians also own the *negative* external effects of a nefarious Indian, so that all Indians should be punished if one Indian commits a murder overseas? What makes the most sense to me is that you own your talents and your shortcomings, and I own mine. This last point regards an assumption about property rights, one that precedes economic analysis. Past AEA president Charles Kindleberger once described this as the debate between those who feel that people should go where they can make the best contribution, and those who feel that people should stay where they belong. I don't think anyone has the right to unilaterally inform you where you belong, and I think the same applies to Indians, Chinese, Filipinos, Malawians --- everyone. I discuss some of these points in more detail in a piece for the Journal of Economic Perspectives that will appear alongside David's, later this year.