It's estimated tens of millions of people may be the victims of modern-day human trafficking. On Tuesday, the International Organization for Migration and the U.N. Office on Drugs and Crime pledged closer cooperation to tackle the problem.

The two agencies have signed an agreement in Vienna to ensure national borders are better managed in what they call an" integrated, modern and humane way."

"We can quote several sources, but there is no concrete and accurate information. It is believed that there are between 12 and 27 million victims of trafficking. This is really something due to the fact that there are no worldwide mechanisms in place to detect appropriately victims of trafficking," said Laurence Hart is the head of the migrant assistance division of the International Organization for Migration.

Big business

The International Labor Organization estimates human trafficking and migrant smuggling is a $32 billion a year industry.

"The idea of a trafficked person used to be basically a stereotype of a woman that was brought into prostitution. Now the profile of a trafficked person is becoming more and more expanded because nowadays we have an increasing number of men, who are trafficked for labor purposes," he said.

For example, many trafficked men from Asia find themselves in the fishing sector in Africa. Many African women have been trafficked to Asia.

Men, women and children may be abducted or lured into trafficking with the promise of a better life.

Hart said, "Often times what happens is that the person, to have specific work, a specific job, has to pay an intermediary. And the intermediary is asking for some money for that and the person does not necessarily have that money. So he says, ‘I will pay you back.' Then that becomes a bond because that debt (is) never paid back or because that debt seems to be never-ending."

Prior to the new agreement, the IOM and the U.N. Office on Drugs and Crime already worked closely in many parts of Africa, as well as Colombia in South America.

"Basically, our cooperation with UNODC is related to capacity building. So, how to strengthen existing referral mechanisms, shelters and training of, for example, the judiciary, the law enforcement and the civil society which are involved in the counter trafficking," he said.

IOM also offers direct assistance to trafficking victims to help them return home.

Consumer goods from forced labor?

Hart said trafficking victims may be forced to manufacture consumer goods. But the companies they work for are often not aware of this.

"We're finding increasingly a number of companies who are asking us how can we make better traceability in our supply chain and make sure that what we sell, what we produce, is not the result in any way of people who are victims of trafficking," he said.

The new agreement also calls for greater response to the problem at the local, regional and international levels. It also aims to increase cooperation with other agencies, including the Global Migration Group and the Inter-Agency Coordination Group against Trafficking in Persons.