In the social innovation field it has been recognized the need for infrastructures to support the flourishing of social innovation: intermediaries that should facilitate the connections between diverse stakeholders and resources. Design research has contributed to the idea of intermediaries by developing the concept of enabling platforms. These are situated systems of human and non-human actors, which should support bottom-up initiatives and cross-sector networks by responding to the meta-technological demands of social innovation activities. In order to fulfil this scope they should be deeply rooted in the specific context where they are operating, valuing local stakeholders and resources. Furthermore they should be characterized by a certain degree of indeterminacy, which leaves to the involved stakeholders the possibility to initiate their own activities by performing design actions after the design of the platform is concluded, the so called design-after-design.