Rainey has been a passionate advocate for human rights for over 30 years, involved in multiple US-based nonprofit organizations confronting issues from housing insecurity, economic hardships, social equity, and modern slavery. She founded Six Delta, an organization that tackles child labor and sex trafficking and works with other global child rescue organizations to remove children from harm. Rainey is the Co-founder of SEAM, is the Lead Author of the SEAM Standard, and currently serves as the organization's CEO.