Contemporary slavery, also sometimes known as modern slavery or neo-slavery, refers to institutional slavery that continues to occur in present-day society. Estimates of the number of enslaved people today range from around 38 million to 49.6 million, depending on the method used to form the estimate and the definition of slavery being used. The estimated number of enslaved people is debated, as there is no universally agreed definition of modern slavery; those in slavery are often difficult to identify, and adequate statistics are often not available.
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 people in forced sexual exploitation, and 4 million people in forced labour imposed by state authorities. An additional 15.4 million people are in forced marriages.
The Office to Monitor and Combat Trafficking in Persons, an agency of the United States Department of State, says that modern slavery', 'trafficking in persons', and 'human trafficking' have been used as umbrella terms for the act of recruiting, harbouring, transporting, providing or obtaining a person for compelled labour or commercial sex acts through the use of force, fraud, or coercion". Besides these, a number of different terms are used in the US federal Victims of Trafficking and Violence Protection Act of 2000 and the United Nations Protocol to Prevent, Suppress and Punish Trafficking in Persons, especially Women and Children, including "involuntary servitude", "slavery" or "practices similar to slavery", "debt bondage", and "forced labor".
According to American professor Kevin Bales, co-founder and former president of the non-governmental organization and advocacy group Free the Slaves, modern slavery occurs "when a person is under the control of another person who applies violence and force to maintain that control, and the goal of that control is exploitation".