The paper examines the impact of immigration and trade on the U.S. labor market, particularly focusing on the effects on less skilled and low-paid workers. Since the 1960s, the number of immigrants relative to native-born workers has increased, with a growing proportion coming from less developed countries (LDCs) and a disproportionate number having relatively little schooling. Trade has also risen, with a larger share of imports coming from LDCs. These changes have increased the effective labor supply of less skilled workers, potentially affecting relative wages and employment. The paper reviews the debate on the distributional effects of immigration and trade, noting that while some analysts stress adverse effects on low-income Americans, others highlight positive economic benefits. It uses the "factor proportions approach" to simulate the impact of immigration and trade on national labor supplies by skill level under different scenarios. The study finds that immigration has had a marked adverse impact on the economic status of the least skilled U.S. workers, while trade has had smaller effects on the overall labor supply of less skilled workers, though these effects vary depending on the technology used in displaced industries. The paper also examines the location decisions of the native population in response to immigration, finding that the influx of immigrants has reduced the flow of natives to primary immigrant-receiving states like California. It discusses the concentration of immigrants in certain geographic areas and the impact of immigration on the labor market outcomes of natives, including wage differentials and employment rates. The analysis suggests that the spatial correlation between changes in native outcomes and immigration is inconsistent, indicating that unobserved factors may dominate the data and that immigration is not a major determinant of regional labor market outcomes for natives. Finally, the paper explores the internal migration of natives in response to immigration, finding that the share of natives living in California has stabilized since 1970, suggesting that the effects of immigration on native location decisions are limited. Overall, the paper concludes that while immigration and trade have significant impacts on the U.S. economy, their effects on labor market outcomes are complex and vary across different regions and skill groups.The paper examines the impact of immigration and trade on the U.S. labor market, particularly focusing on the effects on less skilled and low-paid workers. Since the 1960s, the number of immigrants relative to native-born workers has increased, with a growing proportion coming from less developed countries (LDCs) and a disproportionate number having relatively little schooling. Trade has also risen, with a larger share of imports coming from LDCs. These changes have increased the effective labor supply of less skilled workers, potentially affecting relative wages and employment. The paper reviews the debate on the distributional effects of immigration and trade, noting that while some analysts stress adverse effects on low-income Americans, others highlight positive economic benefits. It uses the "factor proportions approach" to simulate the impact of immigration and trade on national labor supplies by skill level under different scenarios. The study finds that immigration has had a marked adverse impact on the economic status of the least skilled U.S. workers, while trade has had smaller effects on the overall labor supply of less skilled workers, though these effects vary depending on the technology used in displaced industries. The paper also examines the location decisions of the native population in response to immigration, finding that the influx of immigrants has reduced the flow of natives to primary immigrant-receiving states like California. It discusses the concentration of immigrants in certain geographic areas and the impact of immigration on the labor market outcomes of natives, including wage differentials and employment rates. The analysis suggests that the spatial correlation between changes in native outcomes and immigration is inconsistent, indicating that unobserved factors may dominate the data and that immigration is not a major determinant of regional labor market outcomes for natives. Finally, the paper explores the internal migration of natives in response to immigration, finding that the share of natives living in California has stabilized since 1970, suggesting that the effects of immigration on native location decisions are limited. Overall, the paper concludes that while immigration and trade have significant impacts on the U.S. economy, their effects on labor market outcomes are complex and vary across different regions and skill groups.