The previous chapters made clear that designers can more consciously engage in the politics of their collective design work in order to better address the complex societal challenges they care about. This final chapter proposes that if designers want to address these politics, they should go a step further than developing their capabilities to reveal and translate radical interdependencies. They need to explicitly activate these interdepencies, between both human and non-human, spokespersons and implicated actors, and embed them in the diverse set of institutions and collectives that can provide the necessary support for changes to take place. Based on the learnings from the current ontological turn in design, we will coin the attitude that was central in this whole book - that of designing for and with radical interdependence with attention to politics - as “ontologising”. In other words, ontologising supports designers in reflecting on how they can design in a more life-sustaining way with and for the relationships of radical interdependence between all possible human and non-human actors gathered around common matters of care. Based on the analysis of a new set of cases, we observed that to design with this ontologising attitude requires four key capabilities: revealing, translating, activating and embedding the radical interdepencies among and between (more or less ephemeral) collectives and (more or less stable) institutions.