Human trafficking involves the movement of people, within and across borders, through the use of violence, deception or coercion for the purpose of forced labour, servitude, sexual exploitation or slavery-like practices. It is a worldwide phenomenon and the third most profitable criminal activity after drugs and arms trafficking, giving rise to an estimated profit of $7-10 billion in 2003. The risks of getting caught are low because the relationship nurtured by traffickers with their ‘cargo’ is based on violence or threats of violence, making migrants unwilling or unable to contact the authorities.

Women may enter as wives or girlfriends of traffickers. In many cases, they believe themselves to be in genuine relationships until they arrive at their destination and are forced to work in prostitution. Some women may have been abducted, i.e forcibly dumped into the boot of a car but this is relatively rare as traffickers need the co-operation of their victims if they are to be taken across borders without alerting the authorities.

Of the 84 victims of trafficking found during an anti-trafficking police initiative in the UK in 2006, Operation Pentameter, all had entered overtly through airports, ports, rail and coach stations but not necessarily with legal documentation. About 60 per cent of them arrived in the UK illegally, which means the remaining 40 per cent found themselves in these terrible situations despite having arrived in the country legally. Their journeys are therefore not usually as arduous as those of people who have been smuggled across borders. According to the Anti-Slavery report on forced labour, the majority of trafficked workers are here legally, although most of those interviewed came to their attention through channels like the Citizens Advice Bureau and were more likely to be legal than not.