Alpha Delta Sigma

Alpha Delta Sigma (ΑΔΣ) is a professional fraternity in the field of advertising. It was founded on November 14, 1913 as a men's national professional advertising fraternity at University of Missouri.

It merged with Gamma Alpha Chi, which had been formed February 9, 1920 at University of Missouri as a female counterpart to Alpha Delta Sigma, in 1972. In 1964, Alpha Delta Sigma had 50 undergraduate and 11 professional chapters and Gamma Alpha Chi had 37 chapters of which 22 were active.

The merged fraternity was headquartered at Texas Tech University. In 1973, the fraternity was merged into the American Advertising Federation, however the AAF continues to use the name Alpha Delta Sigma for their Collegiate programs for the National Honor Society.