I came across this organization as I was looking for groups who bring together indigenous groups to collectivize their thoughts on issues like sustainability or climate change Tebtebba seems to do this well with a board audience and strong links to the bureaucratic machinery that works it. Here is part of their mission statement:
Tebtebba seeks to promote and disseminate widely indigenous peoples worldviews, their perspectives on key issues such as individual and collective human rights, sustainable development, climate change, biodiversity, traditional knowledge, customary laws and governance, conflict transformation, gender, etc.
And of course… a link to their site: