This paper reviews evidence about the effects of immigration on entrepreneurship and innovation. Thenumber of immigrants has increased both in absolute numbers and as a share of the US population.The countries of origin have shifted from Europe to Latin America and Asia. The share of higherskilledimmigrants has risen, while the share of lower-skilled immigrants has declined. Immigrantstend to be entrepreneurial and to start a significant share of US businesses. Those new firms make asignificant contribution to employment growth in the United States. Research indicates thatimmigrants tend to be innovative. This finding is partially the result of a large percentage ofimmigrants with science, technology, engineering, and math (STEM) degrees. The share of USpatents going to immigrants has significantly increased over time. Immigrant inventors are acomplement to native inventors, thus raising total productivity over time.