Social Service Workers and Social Service Organizations
The U.S. Department of Health & Human Services provides these materials social service workers:

HHS - Identifying and Interacting with Victims of Human Trafficking (in PDF)
HHS - Screening Tool for Victims of Human Trafficking (in PDF)
HHS - The Mindset of a Human Trafficking Victim (in PDF)
HHS - Messages for Communicating with Victims of Human Trafficking (in PDF)
HHS - PowerPoint Presentation for Social Service Organizations (in PPT)
HHS - Social Service Poster #1 (in PDF)
HHS - Social Service Poster #2 (in PDF)
HHS - Social Service Brochure (in PDF)