By Imogen Foulkes
BBC News, Geneva
Countries in South-East Europe are failing to take effective measures against people trafficking, the United Nations Children's Fund (Unicef) says.
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A Unicef report says that while countries in the region have strict anti-trafficking laws they do not tackle the root causes of the problem.
Unicef found that young people at risk often did not know how to protect themselves from traffickers.
Few knew that traffickers were often friends or even family members.
The report looked at trafficking in Albania, Bosnia-Hercegovina, Bulgaria, Croatia, Macedonia, Moldova, Romania and Serbia-Montenegro.
No one knows exactly how many people fall victim to traffickers - it is a secretive and complex business.
But Unicef does know what kind of people are trafficked: young women between the ages of 15 and 17 are sold for sexual exploitation; children under 13 are trafficked for forced labour and begging.
Many countries in South-East Europe have harsh laws against trafficking, but they focus on preventing illegal migration or cracking down on prostitution and organised crime.
What is missing, Unicef says, are child-focused strategies to prevent trafficking in the long term.
Children surveyed in Montenegro, for example, suggested that not walking alone at night might protect them.
In Romania, trafficked children returning from European Union countries are simply sent back to their families by the police, without involving the child protection agency and without investigating the situation of the family concerned.
But there are some success stories. Moldova, Europe's poorest country, has set up community services for abused children and introduced family and life-skill classes for those most at risk.
Education and awareness-raising are, Unicef says, the strategies most likely to prevent trafficking in the long-term. Repressive laws alone will not work.
Deborah McWhinney of Unicef told the BBC that the repressive measures taken were "not empowering - they don't focus necessarily in their response on the human rights of victims, but on preventing the movement of people".
She said NGOs were reporting that the problem of trafficking in South-East Europe had "gone underground, so that we are no longer finding tens or hundreds of women in bars that are being noticed and picked up during raids, but there's just as much trafficking going on in private homes".
Nevertheless, she added that "south-east European countries have shown that they are much more willing to address the issue than many countries in western Europe".