This report examines the emergence, operation and prospects of energy communities (ECs) based on a set of European case studies. It analyses ECs as organisational innovations within energy systems that are themselves in transition. There is a particular focus on the business models (BMs) of ECs, as these offer concise summaries of how communities aim to create, deliver and capture value for their members and for others. Two questions drive the investigation: What makes energy community business models viable? What are energy communities’ prospects for growth? In order to answer these, WP4 of the NEWCOMERS project examined 10 emerging ECs in Germany, Italy, the Netherlands, Slovenia, Sweden and the United Kingdom, over a period of two and a half years. Nine were locally based while one was a ‘virtual community’ of scattered electricity customers, coordinated by an energy company. Each EC operated in differing regulatory and social contexts and relied to varying degrees on specific technologies, skills and external support. The report is based on a mixed-method study of the 10 communities, with data from stakeholder dialogues, surveys, interviews, an international stakeholder workshop, documents and quantitative assessment. The empirical material is framed and interpreted with assistance from the research and grey literature on community and local energy. We have used a 'business model lens' to explore how ECs create and deliver value for stakeholders in energy systems. This approach emphasises the actors and technologies involved in ECs and the value created through their interactions. It has led to an analysis of business model activity systems in which the lens is applied beyond a single focal organisation to consider its relationships with other system actors. Our findings are summarised in terms of emergence and operation of ECs. Based on these, we conclude with some comments on value propositions, the study of EC business models and prospects for ECs in European energy transitions to renewables-based systems.