The issue of how to define public interest is being approached time and again from the various perspectives of the most diverse scholarly disciplines, which is merely the natural outcome of the fact that the understanding of the term “public interest” has far-reaching implications for the functioning of society as a whole,  and indicates whether and to what degree such a society is a democratic society. In determining the public interest, the case law plays a key role; it must interpret public interest within the context of having to protect a great variety of legal relations, and especially in the event of a clash between diverging rights (whether from the area of private law or public law). In determining the public interest, the political and ideological bent of the person who seeks to identify public interest (or decrees its meaning top-down) plays a crucial role. No matter whether one approaches public interest from a liberal, conservative, or even a leftist position: such preconceptions will not only determine the scope of permissible regulatory interferences by the state, but also inter alia the size of the government apparatus – which, after all, is in charge of enforcing public interest. Traditionally, public interest is considered one of the criteria for differentiating between the sphere of private law and that of public law. However, modern society has advanced to a point at which public interest fulfills precisely the opposite purpose, i.e., it ultimately blurs the differences between the two spheres – a development that has been actively fostered by the European Union as a lawmaker, and by the decision-making practice of its authorities. Voices critical of what are known as ‘activist judges’ have made themselves heard, but it appears that in a state under the rule of law, the decisive role in determining public interest and its importance for a viable society and its system of law has fallen to the courts, and will continue to be exercised by the courts.