From sex trafficking within escort services to labor trafficking of farmworkers, the ways humans are exploited differ greatly. Each type has unique strategies for recruiting and controlling victims, and concealing the crime.

For years, we have been staring at an incomplete chess game, moving pieces without seeing hidden squares or fully understanding the power relationships between players. With The Typology of Modern Slavery, our blurry understanding of the scope of the crime is now coming into sharper focus.

To complete this report, Polaris analyzed more than 32,000 cases of human trafficking documented between December 2007 and December 2016 through its operation of the National Human Trafficking Hotline and BeFree Textline—the largest data set on human trafficking in the United States ever compiled and publicly analyzed. Polaris’s research team analyzed the data and developed a classification system that identifies 25 types of human trafficking in the United States. Each has its own business model, trafficker profiles, recruitment strategies, victim profiles, and methods of control that facilitate human trafficking.