Abstrakt:
This article is the first attempt, after the entry into force of the Treaty of Lisbon, to summarize current practice of Early Warning System in Polish Sejm and Senat. Firstly the article presents the issues of early- -warning mechanism for the principle of subsidiarity under the provisions of protocol no 2 on the application of the principles of subsidiarity and proportionality. The article presents the issues common to many national parliaments, as well as experience in the observance of this principle by the other national parliaments, too. The article discusses both substantive and procedural difficulties of parliamentary practice, which occur most frequently. The Author concludes, that if national parliaments would benefit from the competence to control the observance of subsidiarity principle, granted to them under the Lisbon Treaty, they need to strenghten international parliamentary cooperation, focused primarily on the exchange of information.