Phi Sigma Sigma (ΦΣΣ), colloquially known as "Phi Sig," was the first collegiate nonsectarian sorority, welcoming women of all faiths and backgrounds. Founded by 10 women on November 26, 1913, Phi Sigma Sigma is now an international sorority with 60,000 initiated members, 115 collegiate chapters and more than 100 alumnae chapters, clubs and associations across the United States and Canada. The ten young women who founded Phi Sigma Sigma are: Lillian Gordon Alpern, Josephine Ellison Breakstone, Fay Chertkoff, Estelle Melnick Cole, Jeanette Lipka Furst, Ethel Gordon Kraus, Shirley Cohen Laufer, Claire Wunder McArdle, Rose Sher Seidman, and Gwen Zaliels Snyder.

Dedicated to the twin ideals of promoting the brotherhood of man and alleviation of the world’s pain, Phi Sigma Sigma strives to instill the values of leadership through service, lifelong learning and social inclusiveness in today’s young women and future leaders.

In 1918, Phi Sigma Sigma expanded by founding its Beta chapter at Tufts University in Medford, MA, and the Gamma chapter at New York University, although ironically, both of these chapters are inactive as of today. In November 2009, the Delta chapter, at the University at Buffalo, was reinstalled; making it the oldest active chapter. The second oldest active chapter is the Epsilon chapter at Adelphi University, in Garden City, NY, which was recolonized December 6, 2008. While other chapters were founded earlier and have been recolonized, the Xi Chapter at Temple University is the oldest chapter in continuous existence, having never lost its Charter, founded in 1926.