The Adi of India, numbering approximately 120,000 people, are Engaged yet Unreached. They are a generic hill tribe category of Arunachal Pradesh whose name means "hillmen," embracing many subgroups concentrated in the Siang districts. They practice shifting cultivation and follow the indigenous Donyi-Polo religion centered on the sun and moon. They mostly adhere to Ethnoreligion and Hindi is their primary language.