Urban activists advocate for a more just distribution of physical urban space away from motorised traffic towards sustainable, humanscale cities. Some activists act on their own behalf, as concerned or affected residents; others choose to perform specific roles, for instance, as topic experts. This research investigates which roles urban activists perform, how they choose a role, and which motives influence the choice. It asks whether activists' performativity can shift the political landscape in their favour, and how performed roles are perceived by politicians, lobby groups, and the public.