As early as 1940, graduate chapters of Zeta Phi Beta began to realize the importance of the prestige, goodwill, and cooperation of women who, for various reasons, were not members of any Greek-letter organization. 

Under the administration of Soror Lullelia Harrison, the first Amicae chapter was organized in Omaha, Nebraska in 1947 making Zeta the first sorority in the National Pan-Hellenic Council to organize an Auxiliary group. Zeta Amicae is affiliated through local chapters.