The Sigma Phi Society (ΣΦ) is the second Greek fraternal organization founded in the United States and the first to establish a chapter at another college, making it the first national Greek organization.

In North America, fraternities and sororities are social organizations at colleges and universities. They are sometimes collectively referred to as Greek life. Generally, membership in a fraternity or sorority is obtained as an undergraduate student but continues thereafter for life. Some accept graduate students as well. Individual fraternities and sororities vary in organization and purpose, but most share five common elements:Secrecy Single-sex membership Selection of new members based on a two-part vetting and probationary process known as rushing and pledging Ownership and occupancy of a residential property where undergraduate members live A set of complex identification symbols that may include Greek letters, armorial achievements, ciphers, badges, grips, hand signs, passwords, flowers, and colors