https://thewitnetwork.com/
Catalyst
Catalyst is a global nonprofit working with some of the world’s most powerful CEOs and leading companies to help build workplaces that work for women. https://www.catalyst.org/
LeanIn
https://leanin.org/ LeanIn is a primarily volunteer-run organization that hosts events and supports people to start Circles.
Society of Women Engineers
https://swe.org/ SWE has a global presence, largely in the USA. Affiliates exist around the world.