This paper contributes to Strategic Niche Management (SNM), an analytical technique designed to facilitate the introduction and diffusion of radically new sustainable technologies through societal experiments. According to SNM, intensive networking among social actors is a crucial process for the successful incubation of new technologies. However, the manner in which innovation success relates to different characteristics pertaining to the structure and functioning of these actor networks has remained rather unclear. In this paper we open up this ‘black box’ by bringing in social network analysis (SNA), which allows for a more systematic analysis of this issue. We review theoretical SNA contributions that shed light on the link between actor network attributes and innovation outcomes. Then we elaborate a case study about the emerging biofuels sector in Tanzania. After analysing the case from a conventional SNM perspective, we apply SNA techniques to generate more in-depth insights into the composition and functioning of the actor network and how this affects the innovation performance and development prospects of the sector. Policy implications are also discussed.