The threat of climate change, significant growth in the number of prosumers and local energy generation, and the development of new technologies enabling new business models are all contributing to rapid change in the electricity sector. Within this context, peer-to-peer (P2P) trading and energy community (EC) are new, emerging modes of transacting energy that defy the traditional hierarchies based on vertical agreements between energy providers at the retail level and consumers. This article has two interlinked purposes. Firstly, it surveys existing published research that addresses the descriptive and normative legal aspects regarding the design and implementation of P2P trading and EC in the Europe Union. The second purpose of this article is to look forward. Designing and implementing markets for P2P trading and EC are complex challenges. Therefore, this article’s chief contribution is to provide an overview of the various legal issues that could or will arise in the wake of P2P trading and EC. Based on the literature review findings, the article lays out in clear terms the current gaps in knowledge. Our legal reasoning includes both sector-specific regulation and general fields of law. The remainder of the article is structured as follows. Section 2 clarifies the concepts of P2P trading and EC, as used throughout this article. Section 3 develops the literature review in the context of P2P trading. Session 4 does the same for EC. Section 5 concludes.