The Polish constitutional imaginary is an eclectic set of ideas, often contradicting or potentially conflicting with each other. This feature is partly the result of the complexity of Polish history, the leitmotif of which has revolved around regaining and maintaining independence for several centuries. This chapter analyses the relationship between thought, text, and action in the Polish constitutional imaginary about the idea of European integration. Although the EU accession was considered during the constitution-making process, the framers of the Constitution decided not to lay down a typical European clause. Article 90 shapes the intricate relations between two major ineffable ideas: sovereignty and European integration. The lack of coherence between the extensive sphere of thought and the laconic and agonistic nature of the constitutional text has been reflected in action identifying with constitutional practice. European integration has been perceived in the constitutional practice as both an ineffable aspiration and the object of serious concern. Since Poland’s accession to the EU in 2004, for a long time, constitutional practice regarding the EU had been a syncretic collection of cautious friendliness towards EU law, emphasizing (formal) constitutional supremacy and narrowing interpretation of ‘the conferral of competences’. Nevertheless, until recent years the constitutional text had tended to be interpreted as facilitating rather than limiting Poland’s participation in the integration process. Therefore, the recent Eurosceptic turn in the political domain seems unjustified either in the sphere of thought or in the constitutional text. Keywords: European integration, constitutionalism, constitutional imaginary, Poland, illiberalism