This paper explores what is at stake when we talk of language activism, and what normative values often underlie such discussions. Language activism can generally be understood to involve some work in, on or through language (broadly understood), to include some kind of social action (pedagogy, policy, research), and to operate towards some vision of equitable change (social justice). None of these terms, however, is uncontested. If language itself remains an unchallenged ideal, without asking more fundamental questions about whose version of language is involved, language activism may have undesirable effects; if social action remains at the level of institutional advocacy, communities may be poorly served by inappropriate support; and if social justice defines the extent of the political philosophy, language activism may be as reactionary as it is progressive. This paper makes a case for activist applied linguistics – there is little point in applied linguistics otherwise – that by necessity bases its language and politics on emergent rather than extractivist approaches to communities, and on a decolonial agenda for both language and change. A materialist decolonial approach to language activism aims towards collaborative and emergent knowledge and politics.