This purpose of this research was to assess the contribution of skilled immigrants in the creation of engineering and technology businesses and intellectual property in the United States. We found there was at least one immigrant key founder in 25.3% of all engineering and technology companies established in the US between 1995 and 2005 inclusive. We estimate that together, this pool of immigrant-founded companies was responsible for generating more than $52 billion in 2005 sales and creating just under 450,000 jobs as of 2005. This research shows that immigrants have become a significant driving force in the creation of new businesses and intellectual property in the US and that their contributions have increased over the past decade.