With the majority of all H-1B visas going to Indians, we study how US immigration policy coupled with the internet boom affected both the US and Indian economies, and in particular both countries’ IT sectors. The H-1B scheme led to a tech boom in both countries, inducing substantial gains in firm productivity and consumer welfare in both the United States and India. We find that the US-born workers gained $431 million in 2010 as a result of the H-1B scheme. In India, the H-1B program induced Indians to switch to computer science (CS) occupations, increasing the CS workforce and raising overall IT output in India by 5 percent. Indian students enrolled in engineering schools to gain employment in the rapidly growing US IT industry via the H-1B visa program. Those who could not join the US workforce, due to the H-1B cap, remained in India, and along with return-migrants, enabled the growth of an Indian IT sector, which led to the outsourcing of some production to India. The migration and rise in Indian exports induced a small number of US workers to switch to non-CS occupations, with distributional impacts. Our general equilibrium model captures firm-hiring across various occupations, innovation and technology diffusion, and dynamic worker decisions to choose occupations and fields of major in both the United States and India. Supported by a rich descriptive analysis of the changes in the 1990s and 2000s, we match data moments and show that our model captures levels and trends of key variables in validation tests. We perform counter-factual exercises and find that on average, workers in each country are better off because of high-skill migration.