Tau Beta Sigma, National Honorary Band Sorority (ΤΒΣ, colloquially referred to as TBSigma or TBS) is a co-educational service sorority dedicated to serving college and university bands, promoting diversity, and empowering women in bands and the community. ΤΒΣ sisters share the ideals of leadership, educational achievement, appreciation of music, and strong moral values. The Sorority, headquartered at the historic Stillwater Station in Stillwater, Oklahoma, numbers over 3,500 active members in 145 active chapters, and over 40,000 alumni. Since 1946, Tau Beta Sigma has been recognized by Kappa Kappa Psi as "an equal affiliated organization with a parallel purpose, function and role in the college and university band setting", and the two organizations hold joint conventions and Tau Beta Sigm