Abstrakt
The paper deals with one of most vague premises in the civil law systems, i.e. the good and bad faith premise. The purpose of the analysis is to shed light on the very essence of those expressions by analyzing them through the lens of not only civil law but also through general theory of law. The good and bad faith are of importance for acquisition of real estate through adverse possession (usucaption). In order to do justice to the complexity of the issue in question, the paper not only presents the current legal status, but it also dwells upon its legal understanding in the second half of the 20th century. Such structure of the analysis makes it possible to provide an answer as to the reason for introduction of civil rights regulations that are based on the terms that at first glance seem to possess a rather broad semantic base.