When Kathryn Bolkovac was investigating the trafficking of young girls into prostitution in Bosnia ten years ago, she discovered that some of her colleagues were involved.
These were men who worked alongside her for the United Nations, for the US State Department and for the company she was employed by, DynCorp.
When she blew the whistle on this she was fired and had to flee the country. A decade on she's written a book about it. She spoke to HARDtalk's Sarah Montague.
You can watch the full interview on BBC World News on Thursday 27th January 2011 at 0430, 0930, 1530 and 2130 GMT and on BBC News Channel on Thursday 27th January at 2330 GMT and on Friday 28th January at 0430 GMT.
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