This paper examines the reasons women migrate to the United States, with the aim of understanding the vulnerability of such women to human trafficking and modern forms of slavery. El Salvador, Mexico, and Korea are examined, representing three of the four most common countries of origin from among human trafficking victims identified by the US Department of Health and Human Services in 2006. For each of the countries, existing literature is used to explain (1) the pattern of immigration to the US including expectations of remittance from immigrants to family in their home country, (2) the impact of globalization on the country’s economy and labour demand, (3) extra-household inequality, and (4) intra-household inequality. The authors find that women immigrating from El Salvador, Mexico, and Korea are ‘pushed’ from their countries by gender inequalities. Those from Korea are additionally ‘pulled’ to the US by the allure of greater freedom and liberalization in lifestyle. The authors advocate for strengthening social development for women in the country of origin as an alternative to migration, and decriminalization for victims of smuggling, human trafficking, and modern forms of slavery in the US.