Estimates of the number of slaves today range from around 21 million to 46 million, depending on the method used to form the estimate and the definition of slavery being used.  The International Labour Organization estimates that, by their definitions, over 40 million people are in some form of slavery today. 24.9 million people are in forced labor, of whom 16 million people are exploited in the private sector such as domestic work, construction or agriculture; 4.8 million persons in forced sexual exploitation, and 4 million persons in forced labor imposed by state authorities. 15.4 million people are in forced marriage.

These are the different types of slavery today:

Slavery by Descent

Slavery by descent, also called chattel slavery, is the form most often associated with the word “slavery”. In chattel slavery, the enslaved person is considered the personal property (chattel) of someone else, and can usually be bought and sold. It stems historically either from conquest, where a conquered person is enslaved, as in the Roman Empire or Ottoman Empire, or from slave raiding, as in the Atlantic slave trade or Arab slave trade. In the 21st Century, almost every country has legally abolished chattel slavery, but the number of people currently enslaved around the world is far greater than the number of slaves during the historical Atlantic slave trade.

Government-forced Labor

Government-forced labor, also known as state-sponsored labor, is defined by the International Labor Organization as events “which persons are coerced to work through the use of violence or intimidation, or by more subtle means such as accumulated debt, retention of identity papers or threats of denunciation to immigration authorities.” When the threats come from the government the threats can be much different. Many governments that participate in forced labor shut down their connections with the surrounding countries to prevent citizens from leaving. About 35 – 40 countries are currently enforcing military conscription of some sort, even if it is only temporary service.

Penal Labor

Penal labor is a generic term for various kinds of un-free labor which prisoners are required to perform, typically manual labor. The work may be light or hard, depending on the context. Forms of sentence involving penal labor have included involuntary servitude, penal servitude and imprisonment with hard labor. The term may refer to several related scenarios: labor as a form of punishment, the prison system used as a means to secure labor, and labor as providing occupation for convicts. These scenarios can be applied to those imprisoned for political, religious, war, or other reasons as well as to criminal convicts.

Large-scale implementations of penal labor include labor camps, prison farms, penal colonies, penal military units, penal transportation, or aboard prison ships.

Bonded Labor

Bonded labor, also known as debt bondage and peonage, occurs when people give themselves into slavery as a security against a loan or when they inherit a debt from a relative. The cycle begins when people take extreme loans under the condition that they work off the debt. The “loan” is designed so that it can never be paid off, and is often passed down for generations. People become trapped in this system working ostensibly towards repayment though they are often forced to work far past the original amount they owe. They work under the force of threats and abuse. Sometimes the debts last a few years, and sometimes the debts are even passed onto future generations.

Bonded labor is used across a variety of industries in order to produce products for consumption around the world.

Forced Migrant Labor

People may be enticed to migrate with the promise of work, only to have their documents seized and be forced to work under the threat of violence to them or their families. Undocumented immigrants may also be taken advantage of; as without legal residency, they often have no legal recourse. Along with sex slavery, this is the form of slavery most often encountered in wealthy countries such as the United States, Western Europe, and the Middle East.

Sex Slavery

Along with migrant slavery, forced prostitution is the form of slavery most often encountered in wealthy regions such as the United States, Western Europe, and the Middle East. It is the primary form of slavery in Eastern Europe and Southeast Asia, particularly in Moldova and Laos. Many child sex slaves are trafficked from these areas to the West and the Middle East. An estimated 20% of slaves to date are active in the sex industry. Sexual exploitation can also become a form of debt bondage when enslavers insist that victims work in the sex industry to pay for basic needs and transportation.

Many of those who become victims of sex slavery initially do so willingly under the guise that they will be performing traditional sex work, only to become trapped for extended periods of time.

Forced Marriage / Child Marriage

Mainly driven by the culture in certain regions, early or forced marriage is a form of slavery that affects millions of women and girls all over the world. When families cannot support their children, the daughters are often married off to the males of wealthier, more powerful families. These men are often significantly older than the girls. The females are forced into lives whose main purpose is to serve their husbands. This often fosters an environment for physical, verbal and sexual abuse.

Bride-buying is the act of purchasing a bride as property, in a similar manner to chattel slavery. It can also be related to human trafficking.

Child Labor

Children comprise about 26% of the slaves today. Although children can legally engage in certain forms of work, children can also be found in slavery or slavery-like situations. Forced begging is a common way that children are forced to participate in labor without their consent. Most are domestic workers or work in cocoa, cotton or fishing industries. Many are trafficked and sexually exploited. In war-torn countries, children have been kidnapped and sold to political parties to use as child soldiers.

Child soldiers are children who may be trafficked from their homes and forced or coerced by armed forces. The armed forces could be government armed forces, paramilitary organizations, or rebel groups. While in these groups the children may be forced to work as cooks, guards, servants or spies. It is common for both boys and girls to be sexually abused while in these groups.

Fishing Industry

Trafficking victims are often tricked by brokers’ false promises of “good” factory jobs, then forced onto fishing boats where they are trapped, bought and sold like livestock, and held against their will for months or years at a time, forced to work grueling 22-hour days in dangerous conditions. Those who resist or try to run away are beaten, tortured, and often killed. This is commonplace because of the disposability of un-free laborers.

Slavery statistics and information from the U.N. International Labour Organization, Secretariat, United Nations, End Slavery Now, Dalit Freedom Network, The Guardian, Council on Foreign Relations,, Anti-Slavery International, Walk Free, and Chiang Mai City News.