Not an expert, but I was one of those immigrants who took work away from the natural born workers. My understanding is that economists mostly agree that immigration, especially of skilled workers, is generally beneficial to the economy of a country, but perhaps not so beneficial to the local workers who would prefer wages to become inflated due to constrained labor supply. My personal experience was that I got to pay significant US taxes which would otherwise have been paid to another country, then I founded US-based companies that hired natural born employees. Now that I've been a US citizen for 12 years, so I feel that H1-B entrants are reducing my earning potential? Nope. I'd more concerned about smart engineers living in other countries where the cost of living is much lower, who can work remotely, sometimes competing with me for the same work, although to be clear I'm really not concerned about those folks either -- it is hard enough to find good developers in one country that typically one has to expand the net worldwide.