Human Trafficking: How Big Is the Problem?
Due to the underground nature of trafficking, the number of victims is unknown. In 2000, the Victims of Trafficking and Violence Protection Act of 2000 (pdf, 86 pages) asked the U.S. Department of Health and Human Services (HHS) to certify that adults and children (in severe trafficking cases) were victims of human trafficking before these adults and children could receive certain federally funded or federally administered benefits and services.
Since 2001, HHS has issued 1,076 certifications to victims or their representatives in 20 states, the District of Columbia, Guam, and the Northern Mariana Islands. In 2006, certified victims came from more than 40 countries, spanning the Americas, Africa, Asia, Europe, and the Pacific Islands. The majority of victims originated in Latin America (62 percent), with the largest numbers coming from El Salvador (28 percent) and Mexico (20 percent); 97 percent of these victims were female.  Between 2001 and 2005, the United States investigated 555 human trafficking suspects, and by 2005, 78 cases had been terminated with 75 convictions. 
According to U.S. Department of State reports, slave traders prey on vulnerable woman and children, who are often forced into prostitution. Traffickers gain their trust through coercion and trickery. "Very often these ruses involve promises of marriage, employment, educational opportunities, or a better life." 
 U.S. Department of Justice. "Attorney General's Annual Report to Congress on U.S. Government Activities to Combat Trafficking in Persons Fiscal Year 2006," Washington, DC: U.S. Department of Justice, May 2007.
Motivans, M., and T. Kyckelhahn. "Federal Prosecution of Human Trafficking, 2001–2005," Data Brief. Washington, DC: U.S. Department of Justice, Bureau of Justice Statistics, October 2006, NCJ 215248.