Phi Sigma Iota (ΦΣΙ) is an international honor society for students of modern and classical foreign languages and literatures.

Phi Sigma Iota is a member of the Association of College Honor Societies, and awards scholarships to undergraduates and grants to graduate students.

[5][7] At the November 1935 national convention, Phi Sigma Iota merged with Alpha Zeta Pi, a similar society that operated west of the Mississippi River.

[4] In 1978, the society expanded its mission to recognize outstanding achievements in any foreign language, including applied linguistics, bilingual education, classics, comparative literature, and philology.

[6][5] The society's Greek letters Phi, Sigma, and Iota represent Philotès or Friendship, Spoudé or Research and Individuality, and Idioma or Zeal.

[5] Robert E. Dengler, a professor of classics at the Pennsylvania State University, designed the society's insignia, key, and pin which were adopted in 1935.

[5][7] The Forum of Phi Sigma Iota is published annually and includes articles, essays, and poetry written by society members.

[13] Phi Sigma Iota selects qualified members regardless of age, color, disability, gender, national origin, race, religion, or sexual orientation.

[14] Others can be elected to professional membership for contributions to the profession, provided they earned a foreign language degree and ranked in the top 35% of their undergraduate class or a 3.5 GPA as a graduate student.

[14][5] Honorary membership is awarded to individuals outside of the field "who have made distinctive scholarly and research contributions to the study, use, or promotion of foreign languages and the ideals of the society".