The Silicon Valley folks and their allies in think tanks and academia are constantly touting the need to have more immigrants to work as engineers in their companies. This is in spite off the fact that the wages of the workers in the sector do not demonstrate evidence of a serious shortage (i.e. they are not rising rapidly).
Given the frequency with which more immigration comes up in the context of the tech sector, is striking that the issue is not mentioned once in a major NYT article on doctor shortages in the Veterans Affairs hospitals. Doctors in the United States make on average more than twice what their counterparts in other wealthy countries earn, which means that many would likely be willing to work in the United States for a period of time, given the opportunity. (The piece puts the median pay of primary care physicians in the private sector at $221,000 in 2012.) It is also easy to design a mechanism to compensate developing countries for any doctors who come to United States so that they can train 2 or 3 doctors for each one that comes to the United States.
Anyhow, given the evidence of a shortage of doctors in the United States, and the huge gap in pay between the U.S. and other countries, this would seem an obvious case for benefits from increased immigration. It is remarkable that this is not front and center on the national agenda.