Giving Compass' Take:

• Daniela Sala reports how the Syrian refugee crisis has shone a light on sex trafficking in Lebanon, where victims are often treated as criminals.

• How can funders best support the systemic prevention of sex trafficking? 

• Here's the Giving Compass Guide to how donors can make an impact on human trafficking. 

Beirut, Lebanon - "How do I know most of the women working as prostitutes are controlled?" asked Paul, a volunteer for the Jesuits, a religious order of the Roman Catholic Church, before answering his own question. "[Because] the last time I tried to help one of them get in touch with an NGO, I got beaten and threatened by her captors."

Everyone in Lebanon's "sex trade" seems to be involved in trafficking in one way or another: Sources at both the Internal Security Forces (ISF) and the General Directorate of General Security (GS) in Beirut told Al Jazeera that even pimps working further down the chain of command ultimately report to a bigger network of organised traffickers.

Paul has learned the ins-and-outs of Lebanon's trafficking world over the years. Beirut, the Lebanese capital, and Jounieh, a coastal town about 10km (6.2 miles) north of it, are where most victims of sex trafficking end up in Lebanon.

A GS officer estimated that there are at least 800 women and girls who have been forced into prostitution in these areas. But the numbers are hard to verify because of the hidden nature of the problem.

While the ISF formally identified 29 victims - 10 of whom were Lebanese and 13 Syrian - of sex trafficking in 2017, the most recent year for which there is data, other sources, including officers at the International Organisation for Migration (IOM), the United Nations High Commissioner for Refugees (UNHCR) and NGOs, put the number in the thousands.

Read the full article about women sold into sexual slavery in Lebanon by Daniela Sala at Al Jazeera.