The article considers social innovation in an eco-systemic perspective, focusing on policies able to foster it and discussing design’s role within them in terms of professional skills and a widespread capability among all social actors involved. To be expressions of an innovative governance, social innovation policies must themselves be innovative and form policy constellations: clusters of initiatives able to interact positively with the socio-technical system on which they seek to impact. The article is specifically devoted to illustrating the notion of policy constellation, discussing three social innovation policies in Italy: ‘Bologna Regulation’, ‘Milan Smart City’ and ‘Bollenti Spiriti’ in Apulia. All three case studies refer to project strategies that lead to the creation of ecosystems of independent (but mutually synergic) initiatives. Until now, expert design has had a sometimes significant, but generally marginal, presence in this field (mostly as strategic design and, to a lesser extent, as service and communication design). This article suggests that this could and should increase in the future. The authors conclude by posing a new question: what holds together the constituent projects in a social innovation policy? A possible hypothesis is that this something is a cultural frame: a vision of the world shared by all the actors involved
