To compile the largest data set on human trafficking in the United States, 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 the BeFree Textline. From this data analysis, the researchers developed a classification system that identifies 25 types of human trafficking throughout the United States including escort services, domestic work, traveling sales crews, peddling and begging, agriculture, pornography, and commercial cleaning services, among others. Each category has its own business model, trafficker and victim profiles, recruitment strategies, and control methods that facilitate human trafficking. Using this research, stakeholders can begin to develop strategic campaigns to spur systematic action, unite disparate efforts, allocate limited resources, and facilitate effective interventions to combat this traditionally low-risk, high-profit crime. (author abstract modified)