San Diego Zoo Wildlife Alliance is a not-for-profit organization headquartered in San Diego that operates the San Diego Zoo and the San Diego Zoo Safari Park. Founded in 1916 as the Zoological Society of San Diego under the leadership of Harry M. Wegeforth, the organization claims the largest zoological society membership in the world, with more than 250,000 member households and 130,000 child memberships, representing more than half a million people. The organization's mission is to save species worldwide by uniting their expertise in animal care and conservation science with their dedication to inspiring passion for nature. The San Diego Zoo and San Diego Zoo Safari Park feature a combined 15,000 animals of 750 species, not all of which are displayed publicly. In its first few decades, the Zoological Society of San Diego worked to establish and build up the San Diego Zoo. Members of the organization formed groups that later became the Association of Zoos and Aquariums (AZA) and American Association of Zoo Keepers. Wikipedia Member, World Association of Zoos & Aquariums (WAZA) Nonprofit 501(c)(3) organization / San Diego Zoo Wildlife Alliance / EIN: 95-1648219