One woman's story of being trafficked from Sri Lanka
An undercover investigation by BBC Wales Investigates has shown the extent and scale of labour exploitation and modern day slavery in the UK.
With a 300% rise in recorded slavery victims since 2012, officials acknowledge there is a growing problem.
We have seen evidence of traffickers forcing vulnerable people to work for little or no money.
This video is part of a programme - People for Sale - which can be viewed on the BBC iPlayer.