ABSTRACT: Positive Energy Districts (PEDs) constitute an emerging energy transition paradigm, with an ambitious timeline for rapid upscaling to match the urgency of climate mitigation and adaptation. Increasingly networked and coordinated actors aim to realise 100 PEDs across Europe by 2025. This resonates with the mission orientation turn of the European Green New Deal, to inspire and enable target-driven innovation. Yet it raises questions that have long perplexed scholars and practitioners in energy transitions: how can rapid diffusion be achieved in a sustained and replicable manner in diverse socio-technical contexts? Identifying the key questions to address and implement fit-to-purpose solutions within short-term project timescales is...