Most of the roughly 7, 000 languages still existing today are used by ethnic minority groups, in communities of fewer than 100, 000 people. Yet such communities are often bypassed by dominant discourses of ethno-cultural diversity, at the same time as threats to the sustainability of their languages and lifeways have reached historically extreme levels. What do societies stand to gain through the inclusion of ethnic minority cultures and languages, and what is lost when they cease to be? How can linguistic knowledge be applied to support the vitality of ethno-linguistic minority communities, and by whom?