This article questions radical planning’s insistence on an ontological distinction between lay and expert knowledge. Drawing on an in-depth analysis of citizen collectives in Santiago, Chile, I explain how citizen organisations, in their quest for political recognition and emancipation, embrace rationalistic, bureaucratic, formal and instrumental knowledge and tactics. Utilising insights from Science and Technology Studies, I call modes of technification the specific and differentiated strategies by which these collectives become technical entities. Three of these modes are described: the organisational, epistemic and generative modes. The larger claim is that radical planning, by pursuing a politics of difference, may end up enacting a world in which identities are essentialised and roles forcefully allocated.