Only one out of 100 people are rescued from human trafficking according to a senior UN official working on the issue.
Simone Monasebian is head of the United Nations Office on Drugs and Crime (UNODC) in New York.
Victims of human trafficking include those in arranged marriages; forced labour, sexual exploitation, child labour, child soldiers, and even those whose bodily organs are stolen.
The UN marks the World Day Against Trafficking in Persons each 30 July.
Laura Jarriel asked Ms Monasebian what made human trafficking such a pernicious crime.