This article argues that festival innovation is a highly cooperative endeavour among many actors in an inter-organizational network. The aim is to understand how collaborative festival innovation is performed and who takes part in the process. Material from case studies of three Swedish festivals showed that innovation takes place in complex networks involving many actors having various interests. Innovation networks are often highly dynamic and changing: innovation often takes place in new partnerships. The innovation work is hard to plan: it is to a large degree an emergent process and sometimes innovation originates from improvisation. Some innovation can, however, become institutionalized and embedded in the routines of the partnership interaction. Festival organizers need to reflect on their network and relate strategically to how their partners can contribute to successful festival innovation.