Since 2009, Lisa Kristine has been documenting the lives of people caught up in slavery. Her images are shocking, powerful, in-your-face. Yet they are also dignified portraits of those with no choice. Take a look at 17 of her photographs.
We asked an international group of 12 artists, designers, photographers and activists to provide one image that encapsulates what inequality means to them — and to explain their selection. The results are stunning and thought-provoking. Warning: some of them might make you cry.