Harmonizacja prawa prywatnego. Na drodze do jednolitego prawa umów w Unii Europejskiej

The article contains a historical review of selected problems in the sphere of harmonization of the private law in the European Union. The author concentrates primarily on presenting the process of development of the thought of creating uniform regulations concerning the law of contracts in the member states of the EU, beginning with one of the most significant initiatives of establishing the common trade law which was proposed by Ole Lando, whose result were the Principles of European Contract Law, through initiatives of the European Council and European Commission, into the formation of the Common Frame of Reference. The article brings closer some aspects of the establishment of the Acquis Group and the Study Group, results of their work, as well as the scientific and political relation on the part of European institutions towards both the existing and new initiatives within harmonization of the contract law. Moreover, the author presents the gradually growing intensity in the interest on the part of scientific environments, member states and the European legislature in the issue of common regulations concerning contract law in the European Union, and then in the result of these efforts in the form of The Resolution on a Common European Sales Law published by the European Commission in February 2014.