The International Day for the Abolition of Slavery, 2 December, marks the date of the adoption, by the General Assembly, of the United Nations Convention for the Suppression of the Traffic in Persons and of the Exploitation of the Prostitution of Others (resolution 317(IV) of 2 December 1949).

The focus of this day is on eradicating contemporary forms of slavery, such as trafficking in persons, sexual exploitation, the worst forms of child labour, forced marriage, and the forced recruitment of children for use in armed conflict.

According to the International Labour Organization (ILO), there are currently an estimated 21 million forced labour victims worldwide, creating US$ 150 billion in illegal profits in the private economy each year.

ILO has adopted a new legally binding Protocol designed to strengthen global efforts to eliminate forced labour, which is set to enter into force in November 2016.

The 50 for Freedom campaign aims to persuade at least 50 countries to ratify the Forced Labour Protocol by 2018. 

Globally, the industry is vast. Some 35.8 million people are trapped in slavery worldwide, according to an index compiled by the Australian-based Walk Free Foundation. From entire villages of brick makers in northern India, to the forced cotton pickers of Uzbekistan, collectively they earn their handlers $150bn a year in illicit income.

More than two-thirds of the world’s slaves live in just 10 countries. India is the worst offender in absolute numbers, while Mauritania, where slave status is inherited, has the greatest level of slavery per capita. An estimated 4 per cent of the country’s population remains held under the control of traditional masters, with no freedom to own land or to inherit anything from their own families.

While some forms of slavery, such as sex trafficking, are relatively obvious; others are more opaque. From forced or bonded labour, where people are trapped in work by debts against their job, to the sale of a young girl into marriage to settle a loan; slavery comes in many shades. You can read more examples by clicking the Slavery: a modern trade.