Donald Trump and skilled immigration (H-1B visas, green cards)
On skilled immigration, Donald Trump - at least at this moment in time - appears to support two somewhat separate positions, both of which are problematic:
1. Trump supports mass skilled immigration via colleges. That involves turning foreigners who've just graduated from U.S. colleges into legal immigrants. What Trump wants is what Mitt Romney, Michael Bloomberg, and others have called "stapling a green card to their diploma". Even if Trump hasn't used those same words, what they want is the same. The huge problems with that plan are discussed on the skilled immigration page. Trump would braindrain struggling foreign countries at the same time as encouraging U.S. colleges to turn into highly-profitable green card mills for wealthy foreigners.
2. The second involves temporarily bringing in foreign workers from abroad as non-immigrants using the H-1B visa program. Some of the non-immigrants may return home and others may apply to become immigrants. See the entries on the H1B page for the problems with that program. Trump claims he opposes "rampant, widespread H-1B abuse" involved in that program, specifically for lesser-skilled temporary workers. Trump claims he'd end "outrageous practices such as those that occurred at Disney in Florida when Americans were forced to train their foreign replacements" . Those are good things to say, but it would be better for Trump to either oppose the H-1B program entirely or to want to sharply limit it.
Both Trump plans would still allow companies like Facebook, Google Corporate, Microsoft, and hundreds more to game the system to drive Americans out of work. In fact, Trump has contradicted the immigration plan on his website by claiming to want to help Mark Zuckerberg and others obtain talent .
See the last link for a discussion of Trump's policy paper,  for what Trump said at the March 3, 2016 debate, and  for more Trump quotes.
UPDATE: Video from CPAC of Trump promoting his plan: t . co/TWnBKefF7r
 After the March 3, 2016 debate, the Trump campaign released this at donaldjtrump . com/press-releases/donald-j.-trump-position-on-visas:
Megyn Kelly asked about highly-skilled immigration. The H-1B program is neither high-skilled nor immigration: these are temporary foreign workers, imported from abroad, for the explicit purpose of substituting for American workers at lower pay. I remain totally committed to eliminating rampant, widespread H-1B abuse and ending outrageous practices such as those that occurred at Disney in Florida when Americans were forced to train their foreign replacements. I will end forever the use of the H-1B as a cheap labor program, and institute an absolute requirement to hire American workers first for every visa and immigration program. No exceptions.
 At the October 2015 CNBC debate, Trump said:
I was not at all critical of [Mark Zuckerberg]. I was not at all. In fact, frankly, he’s complaining about the fact that we’re losing some of the most talented people. They go to Harvard. They go to Yale. They go to Princeton. They come from another country and they’re immediately sent out.
I am all in favor of keeping these talented people here so they can go to work in Silicon Valley.
 From the March 3, 2016 debate:
MEGYN KELLY: Mr. Trump, your campaign website to this day argues that more visas for highly skilled workers would, quote, "decimate American workers". However, at the CNBC debate, you spoke enthusiastically in favor of these visas. So, which is it?
DONALD TRUMP: I'm changing. I'm changing. We need highly skilled people in this country, and if we can't do it, we'll get them in. But, and we do need in Silicon Valley, we absolutely have to have.
So, we do need highly skilled, and one of the biggest problems we have is people go to the best colleges. They'll go to Harvard, they'll go to Stanford, they'll go to Wharton, as soon as they're finished they'll get shoved out. They want to stay in this country. They want to stay here desperately, they're not able to stay here. For that purpose, we absolutely have to be able to keep the brain power in this country.
KELLY: So you abandoning the position on your website...
TRUMP: ... I'm changing it, and I'm softening the position because we have to have talented people in this country.
 breitbart . com/big-government/2016/03/04/