Editing Office- New York 

As the first ever human rights issue to provoke wide international outrage, slavery is perpetuated by traditional practices such as child and forced marriage, and by the fact that almost half the countries in the world have yet to criminalize it.According to the latest UN figures, 40 million people were living in a state of modern slavery in 2016. 

One in four children are in forced labour, and about 98 per cent of women who are in forced labour have also been subjected to sexual exploitation.Deeply rooted in fear, with victims often “not realizing” they’re enslaved, it becomes "invisible", and "clandestine”, leaving victims unprotected, said Urmila Bhoola, Special Rapporteur on Contemporary Forms of Slavery, who sat down with UN News's Ana Carmo to talk through its causes and consequences. 

 Audio: Ana Carmo, UN NewsPhoto: A Nigerian girl, pregnant with twins after being forced into prostitution following her arrival in Italy via the Mediterranean Sea route from Libya, stands in a home run by an Italian NGO where she is being sheltered in Asti, Piedmont region, Italy. (2017)Credit: UNICEF/Alessio Romenzi