Sigma Gamma Rho Sorority, Inc. was established in Indianapolis, Indiana, on November 12, 1922. It was founded by seven pioneering educators: Mary Lou Allison Gardner Little, Dorothy Hanley Whiteside, Vivian Irene White Marbury, Nannie Mae Gahn Johnson, Hattie Mae Annette Dulin Redford, Bessie Mae Downey Rhoades Martin, and Cubena McClure. Officially incorporated as a national collegiate sorority on December 30, 1929, with the charter of the Alpha chapter at Butler University, the organization has since cultivated a distinguished reputation for fostering positive change within communities through sisterhood, leadership, and service.

Over its history, Sigma Gamma Rho has welcomed over 100,000 collegiate and professional women from diverse fields. With over 500 chapters spanning across the United States, Bahamas, Bermuda, Canada, Germany, South Korea, the U.S. Virgin Islands, and the United Arab Emirates, the sorority extends its reach globally. Additionally, affiliated groups such as the Rhoer Club Affiliates (for teenage girls) and Philos Affiliates (for friends of the sorority) actively support alumnae chapters in various service initiatives and programs.

Central to Sigma Gamma Rho's ethos is its motto, "Greater Service, Greater Progress," exemplified through its extensive community outreach efforts nationally and internationally. Through a myriad of programs, partnerships, and sponsorships, the sorority remains steadfast in its dedication to advancing education, service, and leadership development for the betterment of society. In 2004, the National Headquarters relocated from Chicago, Illinois, to its current residence in Cary, North Carolina. The commitment and achievements of Sigma women are celebrated through publications like The AURORA and various prestigious awards, reflecting their ongoing pursuit of personal and collective success.