The trafficking of human beings is the recruitment, transportation, harbouring, or receipt of people for the purpose of exploitation. It is estimated to be a $5 to $9 billion-a-year industry.Trafficking victims typically are recruited using coercion, deception, fraud, the abuse of power, or outright abduction. Threats, violence, and economic leverage can often make a victim consent to exploitation.

Exploitation includes forcing people into prostitution or other forms of sexual exploitation, forced labour or services, slavery or practices similar to slavery, servitude or the removal of organs. For children exploitation may also include forced prostitution, illicit international adoption, trafficking for early marriage, or recruitment as child soldiers, beggars, for sports (such as child camel jockeys or football players), or for religious cults.

Victims are sometimes tricked and lured by false promises or physically forced. Some traffickers use coercive and manipulative tactics including deception, intimidation, feigned love, isolation, threat and use of physical force, debt bondage, other abuse, or even force-feeding with drugs to control their victims.

People who are seeking entry to other countries may be picked up by traffickers, and misled into thinking that they will be free after being smuggled across the border. In some cases, they are captured through slave raiding, although this is increasingly rare.

Trafficking is fairly lucrative industry. In some areas, like Russia, Eastern Europe, Hong Kong, Japan, and Colombia, trafficking is controlled by large, powerful organizations. However, the majority of trafficking is done by networks of smaller groups that each specialize in a certain area, like recruitment, transportation, advertising, or retail. This is very profitable because little startup capital is needed, and prosecution is relatively rare.

Trafficked people are usually the most vulnerable and powerless minorities in a region. They often come from the poorer areas where opportunities are limited, they often are ethnic minorities, and they often are displaced persons such as runaways or refugees (though they may come from any social background, class or race).

Trafficking of children often involves exploitation of the parents' extreme poverty. The latter may sell children to traffickers in order to pay off debts or gain income or they may be deceived concerning the prospects of training and a better life for their children. In West Africa, trafficked children have often lost one or both parents to the African AIDS crisis.

The adoption process, legal and illegal, results in cases of trafficking of babies and pregnant women between the West and the developing world. In David M. Smolin’s papers on child trafficking and adoption scandals between India and the United States,he cites there are systemic vulnerabilities in the intercountry adoption system that makes adoption scandals predictable.

Women, who form over 80% of trafficking victims, are particularly at risk to become involved in sex trafficking. Potential kidnappers exploit lack of opportunities, promise good jobs or opportunities for study, and then force the victims to become prostitutes, participate in pornography[citation needed] or escort services. Through agents and brokers who arrange the travel and job placements, women are escorted to their destinations and delivered to the employers. Upon reaching their destinations, some women learn that they have been deceived about the nature of the work they will do; most have been lied to about the financial arrangements and conditions of their employment; and all find themselves in coercive and abusive situations from which escape is both difficult and dangerous.

The main motive of a woman (in some cases an underage girl) to accept an offer from a trafficker is better financial opportunities for herself or her family. In many cases traffickers initially offer ‘legitimate’ work or the promise of an opportunity to study. The main types of work offered are in the catering and hotel industry, in bars and clubs, modeling contracts, or au pair work. Traffickers sometimes use offers of marriage, threats, intimidation and kidnapping as means of obtaining victims. In the majority of cases, the women end up in prostitution. Also some (migrating) prostitutes become victims of human trafficking. Some women know they will be working as prostitutes, but they have an inaccurate view of the circumstances and the conditions of the work in their country of destination.

Men are also at risk of being trafficked for unskilled work predominantly involving hard labor. Other forms of trafficking include bonded and sweatshop labor, forced marriage, and domestic servitude. Children are also trafficked for both labor exploitation and sexual exploitation. On a related issue, children are forced to be child soldiers.

Many women are forced into the sex trade after answering false advertisements, and others are simply kidnapped. Thousands of children from Asia, Africa, and South America are sold into the global sex trade every year. Often they are kidnapped or orphaned, and sometimes they are actually sold by their own families.

United States State Department data "estimated 600,000 to 820,000 men, women, and children [are] trafficked across international borders each year, approximately 80 percent are women and girls and up to 50 percent are minors. The data also illustrate that the majority of transnational victims are trafficked into commercial sexual exploitation." Due to the illegal nature of trafficking and differences in methodology, the exact extent is unknown.

Since the fall of the Iron Curtain, the impoverished former Eastern bloc countries such as Albania, Moldova, Romania, Bulgaria, Russia, Belarus and Ukraine have been identified as major trafficking source countries for women and children. Young women and girls are often lured to wealthier countries by the promises of money and work and then reduced to sexual slavery. It is estimated that 2/3 of women trafficked for prostitution worldwide annually come from Eastern Europe, three-quarters have never worked as prostitutes before. The major destinations are Western Europe (Germany, Italy, Netherlands, Spain, UK, Greece), the Middle East (Turkey, Israel, the United Arab Emirates), Asia, Russia and the United States. An estimated 500,000 women from Central and Eastern Europe are working in prostitution in the EU alone.

An estimated 14,000 people are trafficked into the United States each year, although again because trafficking is illegal, accurate statistics are difficult.According to the Massachusetts based Trafficking Victims Outreach and Services Network (project of the nonprofit MataHari: Eye of the Day) in Massachusetts alone, there were 55 documented cases of human trafficking in 2005 and the first half of 2006 in Massachusetts.In 2004, the Royal Canadian Mounted Police (RCMP) estimated that 600-800 persons are trafficked into Canada annually and that additional 1,500-2,200 persons are trafficked through Canada into the United States.

In the United Kingdom, 71 women were known to have been trafficked into prostitution in 1998 and the Home Office recognized that the scale is likely greater as the problem is hidden and research estimates that the actual figure could be up to 1,420 women trafficked into the UK during the same period.Trafficking in people is increasing in Africa, South Asia and into North America.

Russia is a major source of women trafficked globally for the purpose of sexual exploitation, Russian women are in prostitution in over 50 countries. Annually, thousands of Russian women end up as prostitutes in Israel, China, Japan or South Korea. Russia is also a significant destination and transit country for persons trafficked for sexual and labor exploitation from regional and neighboring countries into Russia, and on to the Gulf states, Europe, Asia, and North America.

In poverty-stricken Moldova, where the unemployment rate for women ranges as high as 68% and one-third of the workforce live and work abroad, experts estimate that since the collapse of the Soviet Union between 200,000 and 400,000 women have been sold into prostitution abroad — perhaps up to 10% of the female population. In Ukraine, a survey conducted by the NGO La Strada Ukraine in 2001-2003, based on a sample of 106 women being trafficked out of Ukraine found that 3% were under 18, and the US State Department reported in 2004 that incidents of minors being trafficked was increasing. It is estimated that half million Ukrainian women were trafficked abroad since 1991 (80% of all unemployed in Ukraine are women).

The ILO estimates that 20 percent of the five million illegal immigrants in Russia are victims of forced labor, which is a form of trafficking. However even citizens of Russian Federation have become victims of human trafficking. They are typically kidnapped and sold by police to be used for hard labor, being regularly drugged and chained like dogs to prevent them from escaping. There were reports of trafficking of children and of child sex tourism in Russia. The Government of Russia has made some effort to combat trafficking but has also been criticized for not complying with the minimum standards for the elimination of trafficking.

The majority of child trafficking cases are in Asia, although it is a global problem.

In Asia, Japan is the major destination country for trafficked women, especially from the Philippines and Thailand. The US State Department has rated Japan as either a ‘Tier 2’ or a ‘Tier 2 Watchlist’ country every year since 2001 in its annual Trafficking in Persons reports. Both these ratings implied that Japan was (to a greater or lesser extent) not fully compliant with minimum standards for the elimination of human trafficking trade. There are currently an estimated 300,000 women and children involved in the sex trade throughout Southeast Asia. It is common that Thai women are lured to Japan and sold to Yakuza-controlled brothels where they are forced to work off their price.

Many of the Iraqi women fleeing the Iraq War are turning to prostitution, while others are trafficked abroad, to countries like Syria, Jordan, Qatar, the United Arab Emirates, Turkey, and Iran. In Syria alone, an estimated 50,000 Iraqi refugee girls and women, many of them widows, are forced into prostitution. Cheap Iraqi prostitutes have helped to make Syria a popular destination for sex tourists. The clients come from wealthier countries in the Middle East - many are Saudi men. High prices are offered for virgins.

As many as 200,000 Nepali girls, many under 14, have been sold into the sex slavery in India. Nepalese women and girls, especially virgins, are favored in India because of their light skin.

In parts of Ghana, a family may be punished for an offense by having to turn over a virgin female to serve as a sex slave within the offended family. In this instance, the woman does not gain the title of "wife". In parts of Ghana, Togo, and Benin, shrine slavery persists, despite being illegal in Ghana since 1998. In this system of slavery, sometimes called trokosi (in Ghana) or voodoosi in Togo and Benin, or ritual servitude, young virgin girls are given as slaves in traditional shrines and are used sexually by the priests in addition to providing free labor for the shrine.

Reporters have witnessed a rapid increase in prostitution in Cambodia, Bosnia, and Kosovo after UN and, in the case of the latter two, NATO peacekeeping forces moved in. Peacekeeping forces have been linked to trafficking and forced prostitution. Proponents of peacekeeping argue that the actions of a few should not incriminate the many participants in the mission, yet NATO and the UN have come under criticism for not taking the issue of forced prostitution linked to peacekeeping missions seriously enough.

In the western world, Canada in particular has a major problem with modern-day sexual slavery. In a 2006 report the Future Group, a Canadian humanitarian organization dedicated to ending human trafficking, ranked eight industrialized nations and gave Canada an F for its "abysmal" record treating victims. The report, titled "Falling Short of the Mark: An International Study on the Treatment of Human Trafficking Victims", concluded that Canada "is an international embarrassment" when it comes to combatting this form of slavery.

The report's principal author Benjamin Perrin wrote, "Canada has ignored calls for reform and continues to re-traumatize trafficking victims, with few exceptions, by subjecting them to routine deportation and fails to provide even basic support services."

In the report, the only other country to flunk was the United Kingdom, which received a D, while the United States received a B+ and Australia, Norway, Sweden, Germany and Italy all received grades of B or B-. The report criticizes former Liberal Party of Canada cabinet ministers Irwin Cotler, Joe Volpe and Pierre Pettigrew for "passing the buck" on the issue.

Commenting on the report, the then Minister of Citizenship and Immigration, Monte Solberg told Sun Media Corporation, "It's very damning, and if there are obvious legislative or regulatory fixes that need to be done, those have to become priorities, given especially that we're talking about very vulnerable people."