The first Global Slavery Index, created with the aim of raising awareness about the persistence of slavery and helping governments tackle it, estimates that 30 million people are today living as slaves. Many of these modern-day slaves have been trafficked into sex work and unskilled labour.
According to the report, 10 countries account for 76 percent of that figure - India, China, Pakistan, Nigeria, Ethiopia, Russia, Thailand, the Democratic Republic of Congo, Myanmar and Bangladesh.
In terms of countries with the highest proportion of slaves, Mauritania, where four percent of the 3.4 million-strong population is said to be held in slavery, tops the list, followed by Haiti, Pakistan, India and Nepal.
Think of this in terms of an epidemic. If we don't have the right kind of epidemiological information - where the problem is, the extent of the problem, the types of slavery that we face, as well as the appropriate … intervention ... - how are we are going to be able to solve this? And if we can't measure over time whether or not we are making progress, then it's going to be a very tough problem to solve. So the index is going to work like a yardstick and make sure that we are able to know year on year if we are making progress and to learn what are the best ways to fight slavery.
India is home to almost 14 million slaves, many of whom, the report says, are enslaved by other Indians through debt bondage and bonded labour.
But what does slavery mean today?
A slave is defined as someone who is forced to work through mental or physical threat, owned or controlled by an employer, dehumanised, treated as a commodity or bought or sold as property, or anyone who is physically constrained or has their freedom of movement restricted.
Slavery can take on different forms, including debt bondage, where people become bonded labourers to pay off a loan for which the amount owed, in most instances, never depreciates. Others are born into slavery with the status passed from mother to child in what is known as descent-based slavery, while many are trafficked into slavery.
It is something that effects men, women and children. Many child slaves are used as domestic workers, forced into labour, trafficked for sexual exploitation or used as child soldiers. Then there are the women and children forced into marriage. This category is often also coerced into sexual and domestic work.
Slavery exists in one form or another in almost every country.
Gulf countries - particularly Saudi Arabia, Qatar and the UAE - have been accused of exploiting migrant workers, stripping them of their rights and forcing them into hard labour.
In parts of Africa, young boys are often sold as child soldiers and the girls as prostitutes.
In Eastern Europe, crime gangs have tricked - or sometimes simply abducted - young women and smuggled them into places like Britain and Italy, where they are forced to work in brothels.
So, just how hard is it to stamp out such a lucrative business?
To discuss this, Inside Story, with presenter Jane Dutton is joined by guests: Kevin Bales, the lead author of the Global Slavery Index; Monique Villa, the CEO of Thomson Reuters Foundation; and Benjamin Skinner, an investigative journalist who has infiltrated trafficking circles.
"I believe that slavery should belong to history books, and most of the people around the world think it still belongs to history books. But in reality that is not at all the case. Slavery is growing by the year .... Now that we will have more and more data we will have more means to fight slavery."
Monique Villa, the CEO of Thomson Reuters Foundation