Certain forms of migration are desired in many receiving countries for their presumed positive economic effects. This is probably most obvious in the case of talented and highly educated people who work in highly productive science and technology sectors. If a country succeeds in attracting more such people, it may also more easily attract more highly productive industry and generate more innovation. This in turn increases the country's average productivity, incomes and tax revenues, which benefits its entire population. Most likely, virtually no one in the country loses from this. These people have an excellent labor market. They do in most cases not compete for jobs as much as they help each other to create productive and innovative environments, where they gain from the presence of each other. This, most of all, is why high-tech industry clusters geographically, such as most famously in Silicon Valley.

If there are losers from the migration of these people, they would be their countries of origin, who lost them, and other potential destination countries, who did not get them either. Western countries compete with each other to attract them. I will treat this in some more detail in Chapter 8. Here it suffices to say that this type of immigration is looked positively upon by almost everybody.

Another category of immigration that is viewed positively at least by most people is that which helps to more easily fill labor shortages. If an economy otherwise has good potential for further productivity development, yet is held back by shortage of workers in certain sectors (quite often this will be the construction sector, where labor demand is highly volatile), an inflow of workers from abroad may ease the bottleneck and allow productivity, incomes and tax revenues to increase more broadly in the economy. This is to almost everyone’s gain, although the domestic workers who were previously in short supply may have been deprived of some spectacular short-term income increases. (On the other hand, if many immigrant workers leave again in the next economic downturn, these domestic workers may eventually become winners too, as it makes an unemployment increase affect them less strongly.)