One advantage of photography is that it's visual and can transcend language.

Slavery is illegal everywhere, but it exists all over the world.

When people think of slavery, they think of an era from the distant past. Grainy photographs from Civil War times. And yet it goes on.

Around the world, human traffickers trick many people into slavery by false promises of good jobs or good education, only to find themselves forced to work without pay, under the threat of violence.

There are more than 27 million people enslaved in the world today - that's double the amount of people taken from Africa during the entire trans-Atlantic slave trade.

One advantage of photography is that it's visual and can transcend language.

I see myself as a witness to humanity.