Ayahuasca has a rich and complex cultural heritage, but today, the use of unfamiliar indigenous plant preparations across the continent presents novel challenges. Although it is not subject to international control, recently, the number of arrests and prosecutions related to ayahuasca has rapidly increased, and the current legal situation is complex and fraught with uncertainty. This chapter aims to trace the background constellation of laws, legal cases, appeals, and debates that, together, can sketch an outline explaining how ayahuasca has arrived at the legal position it currently occupies and what the future could potentially hold. This chapter involves a close study of both reported and unreported proceedings in the courts regarding ayahuasca and other plant psychedelics. It includes discussion of a variety of legal texts as well as valuable information gleaned from personal communication with defendants, lawyers, and other actors. By examining these sources, it is possible to clarify why the legality of ayahuasca is so difficult to pinpoint as well as the reflexive implications of this complexity on determining the outcome of future cases. Despite binding judgments from the appellate courts, evolving prosecution strategies and recent legislation mean that the pervading uncertainty is no closer to a meaningful resolution. A thorough consideration of the legal and social history from across Europe aims to provide a useful summary of the challenges to both ayahuasca users and jurisprudence scholars.