Renewable energy communities are a growing and extraordinarily multifaceted phenomenon which involves a range of possible activities around renewable energy (production, supply, distribution, sharing and consumption) collectively carried out by citizens, often in partnership with small and medium enterprises and local public authorities. Being a new technological solution in the world of energy, it is essential to have a clear understanding of what they consist of, who can be part of them and why they are important for achieving a sustainable future. This thesis work aims to deal with the issue of energy communities in their entirety, starting from basic aspects, then focusing on the topic of the statute and on how to define the criteria for dividing incomes within the community, given the different nature of the participants.