Theta Sigma Upsilon (ΘΣΥ) was an American sorority founded on March 25, 1921 at Emporia State University.

Theta Sigma Upsilon was founded on March 25, 1921 at Emporia State University.

[2] In 1925, the sorority became part of the Association of Education Sororities which it remained a member until the association dissolved when its members became part of the National Panhellenic Conference.

[1][3] Alpha Gamma Delta absorbed Theta Sigma Upsilon at the 22nd international convention of Alpha Gamma Delta at French Lick, Indiana on June 29, 1959.

[4] Thirteen chapters were added to Alpha Gamma Delta from this merger, with these names as their new ΑΓΔ chapter designations:[5] Theta Sigma Upsilon's colors were rose and silver.