The use of Living Labs is a promising approach to develop and test sustainable system innovations. A Living Lab approach that is yet to be discussed in literature, is that of a Festival Living Lab (FLL). Festivals can be considered as temporary mini societies with systemic sustainability challenges regarding water, energy, housing, logistics, waste management, food and behaviour. Since a festival is built up from scratch every time the event is hosted, adjustments can be made to its overarching system, and mutual interrelations between different aspects of the system can be experimented with. To evaluate the potential of FLLs as effective real-life experimentation settings for sustainable system innovation we present the Living Lab Activity Framework (LLAF), distinguishing various innovation stages and system levels. We deploy the LLAF to evaluate a selection of innovation projects within the DORP Festival Living Lab at the Welcome to The Village festival in The Netherlands, demonstrating that festivals can host various stages of the innovation process on different system levels.@en