Since its inception, Sigma Gamma Rho has promoted unity among women and has worked with individuals who were not members of Greek-lettered organizations. In 1954, the sorority officially approved the organized affiliate group and accepted the name of "Philo"(meaning Friend) as the official name. In 1980, the Sigma Gamma Rho Sorority, Inc. Philo Affiliate was organized on a national level and has since grown to represent over a thousand women organized in the United States and abroad. 

The Philo Affiliates organization is made up of women who are not members of Sigma Gamma Rho but who share its principles and are committed to supporting its mission. Its members engage in a variety of service projects and programs, including educational and cultural initiatives, community outreach, and fundraising. The Philo Affiliate also provides a platform for women to develop leadership skills, build relationships, and contribute to the growth and success of Sigma Gamma Rho Sorority, Inc.