Migrant sex work
Because of their illegal and vulnerable economic status, some migrant sex workers may find themselves in situations where coercion and forced sex work may be present. Under international legal definitions of human trafficking, forced and coercive forms of sex work are considered to be instances of involuntary sex trafficking. However, many scholars caution against categorizing sex workers as either completely voluntary or completely involuntary. They often argue that sex work, like other forms of labor, can span a spectrum between the two extremes, with most circumstances falling in the middle through various labor rights violations. Nevertheless, the vulnerability of migrant sex workers can make them susceptible to exploitative or coercive labor practices that can resemble or be human trafficking.
Organized crime
Human trafficking for the purpose of sexual exploitation is a major cause of contemporary sexual slavery and is primarily for prostituting women and children into sex industries. Sexual slavery encompasses most, if not all, forms of forced prostitution. The terms "forced prostitution" or "enforced prostitution" appear in international and humanitarian conventions but have been insufficiently understood and inconsistently applied. "Forced prostitution" generally refers to conditions of control over a person who is coerced by another to engage in sexual activity. Official numbers of individuals in sexual slavery worldwide vary. In 2001 International Organization for Migration estimated 400,000, the Federal Bureau of Investigation estimated 700,000 and UNICEF estimated 1.75 million. The most common destinations for victims of human trafficking are Thailand, Japan, Israel, Belgium, the Netherlands, Germany, Italy, Turkey and the United States, according to a report by UNODC.