The most senior Catholic in England and Wales has said the battle against the problem is an opportunity to "put the victim at the centre".
Cardinal Vincent Nichols, who has also described the crime as a "huge problem in the fabric of society", has been overseeing a pioneering project called Santa Marta which brings police, nuns and bishops from across the world together to help tackle it.
Cardinal Nichols said his work got a powerful endorsement from Pope Francis who told him to "keep this going".
The Archbishop of Westminster also said airport coffee staff (below) were being trained to spot signs of human trafficking before victims were taken "underground, where the practice is much more difficult to detect and stop.
Speaking to the Press Association, he said the Catholic Church's child sex abuse scandals have left many untrusting.
He said the Church's past has motivated him to do all he can to work for the victims of modern slavery, many of whom end up being trafficked and sold into sex work.
Cardinal Nichols said: "What in this work we try to do is keep the victim right at the centre.
"So yes it is a terrible crime, and yes there is prosecution to be pursued, and yes it is fascinating listening to people talk about developing instruments that can help banks be aware of where money might be coming from. But we want to keep the victim at the centre of this.
"That is partly because over the last 15 years in my life, and I think in the life of the Catholic Church more broadly, there has been real difficult lessons to learn about understanding victims and opening your heart to victims, and realising how early experiences and experiences of total vulnerability can have a lifelong impact on a person.
"So while for us the most dramatic expression of that has been with childhood abuse, it has, I think, challenged me to understand the perspective of the victim much more."
According to the International Labour Organisation, 21 million people in the world are victims of forced labour and in Britain an estimated 13,000 people work as modern slaves in fields, factories, fisheries, nail bars and prostitution.
The Modern Slavery Act passed in 2015 and introduced a life sentence for those found guilty of the crime.
The UN recently pledged to end modern slavery by 2030.
Cardinal Nichols said that while many slavery victims come from abroad, that's not always the case.
He said: "The very first person I met who suffered this was an English girl who was trafficked and deceived by a relationship with an Italian lad who invited her to Italy."
