The aim of this work is thus to investigate the role of physical space in social innovation activities and projects and its relevance in terms of costs - in the framework of business planning and modelling - and in terms of social impact generated. Despite of the increasing interesting in social innovation, previous studies missed to tackle space as a specific barrier and asset of social innovation activities. In this sense, this research aims at filling a gap in the conceptual framework of social innovation, analysing how physical space is managed in social innovation ventures and to which extent physical space represent not only a physical asset but might generate also intangible assets. The research performed consisted of literature review on social innovation definition, social impact measurement and practices and on the analysis of space as enabling factor of innovation. Through empirical observation of 52 social innovation projects and building of three case studies, the work provides insights on the business models for social innovation projects centered around the acquisition and maintenance of a physical space, the social impact generated by these projects and linked to the physical space and measurement efforts done to assess the social impact