Drawing borders between countries has historically been a very demanding task, often underpinned by deeply-rooted emotions that suppress the argumentative dialogue and reasoning and in too many cases has led to long-term general deterioration of relationships which may devolve into war. As the title suggests, the focal point of this paper will be a legal assessment or a legal prediction of the outcome of the maritime border delimitation dispute between Slovenia and Croatia in the northernmost part of the Adriatic Sea, namely in the Piran Bay. The paper will be structured into four parts. In the first part the authors will present the factual context of the dispute, followed by a presentation of the legal arguments that both countries have laid on the table so far. In the third hermeneutical part, these legal arguments will be applied to the factual context assessed in light of valid international law and especially the existing jurisprudence on international juridical and non-juridical bodies, including the practice of other states in similar cases. In the last part the authors will predict the outcome of the case as if they were the arbitrators or the judges of a tribunal to whom the dispute between Slovenia and Croatia will most likely eventually be referred to.