Not enough is being done to prevent the trafficking of young people in south-eastern Europe, a report by two children's charities says.
Trafficked girls and women are often forced into prostitution
Existing regional programmes fail to tackle the root causes of the problem, the report by the UN children's agency (Unicef) and Terre des Hommes says.
It says thousands of youngsters are smuggled each year to Western Europe to be used in the sex trade or slavery.
The report focuses on victims in Albania, Moldova, Romania and Kosovo.
It also says the British government is not doing enough to prevent the trafficking.
The UN estimates that some 1.2m children are trafficked across the world each year - with about 246m youngsters also thought to be involved in child labour.
In the UK alone, between 1999 and 2003, some 250 children were rescued from trafficking.
The new report - Action to Prevent Child Trafficking in South-Eastern Europe - says prevention efforts by governments in the region, and international and non-governmental organisations, fail to address the root causes of the trafficking.
Report author Mike Dottridge says existing programmes rely too heavily on "unfocused" awareness-raising campaigns, often aimed at adults rather than children.
Some programmes carry stereotypical images of men lurking in the shadows when in reality traffickers are often families or friends, Mr Dottridge says.
He makes the claims after visiting Albania, Moldova, Romania and Kosovo and interviewing 25 child victims of trafficking.
The report says youngsters vulnerable to trafficking need to be given life skills education to teach them how to make decisions and give them greater self esteem.
Agencies, such as the police, immigration officials and social services should be trained to help them identify trafficked children, it says.