
The principle of freedom of contract is one of the guiding principles of modern contract law. It was reflected in different forms and to different extents in the laws of the partitioning powers, applicable in the Polish lands in the era of partitions. After Poland regaining independence, work began on the unification of legal systems, which was an extremely difficult task in terms of substantive law. The work on contract law and the accompanying debate could not ignore the fundamental principle of freedom of contract, which eventually resulted in developing an original solution. It was first captured in Article 55 of the Code of Obligations[1], and then restored, in slightly changed wording, in the Polish legal system in Article 3531 of the Civil Code[2]. Although the principle of freedom of contract was not formally enshrined in the regulations that were effective between 1965 and 1990, it was considered by scholars in the field to be still applicable to a limited extent. From current perspective, this regulation is worth looking at and assessing, especially in the context of its future application. This analysis leads to the conclusion that the existing regulation is generally sufficient and does not need to be amended at the current stage of development of civil law.