GreenNet
Society, Issues, Environment, Organizations - GreenNet. An umbrella site for over 200 green, peace, human rights and development groups.
https://www.gn.apc.org/
Organizations
idealist.org - Welcome to Idealist.org - Imagine. Connect. Act.
Society, Issues, Environment, Organizations - Idealist. Directory of nonprofit and volunteering resources on the Web, with information provided by 16,000 organizations in 130 countries.
https://www.idealist.org/
The Buckminster Fuller Institute
Founded in 1983, the Buckminster Fuller Institute serves a global network of design innovators.
https://www.bfi.org/