It is the official engagement group of the country's G20 leadership representing the voices of non-profit, voluntary citizens' groups in service to society.
It has been inaugurated at Amritapuri in Kerala's Kollam district.
Sri Mata Amritanandamayi Devi (Amma) is the Chair of C20.
There are nine engagement groups on the non-government side of the G20.
These groups make policy recommendations to G20 leaders and help shape them.
Business 20, Civil 20, Labour 20, Parliament 20, Science 20, SAI 20, Startup 20, Think 20, Urban 20, Women 20, and Youth 20 are the nine groups.