Even the most precise statutory provisions cannot guarantee 100% certainty and uniformity in the application of law. Those who apply them sometimes have to go beyond the legal text and seek additional interpretive guidelines. Such guidelines may have different status – they can be formulated in ruling practice, in written law, in legal literature – sometimes they even have an extralegal nature. The purpose of the presentation is to determine what the status of interpretive law is and whether it is uniform or different in different legal cultures. Adopted solutions have an impact on the manner in which court decisions are justified and on the level of citizens’ trust in the state. In my paper, I will consider whether some of the methods of regulating interpretation law can be considered better and some worse, taking into account the aspects already mentioned. Considering the solutions adopted in various countries, I will also consider how the form of regulation affects its content.