Since May 2004 Polish administrative courts have passed a great deal of judgments in which the law of the European Union (formerly European Community law) has played either the main role or a subsidiary role in the proceedings. This article seeks to examine how the above-mentioned courts comply with the expectations which are put on them by EU law and how they participate in the process of legal integration within the EU. In this context, the author scrutinizes how the national judiciary adjudicating in the administrative law area understands, interprets, employs and applies the systemic principles of EU law such as: supremacy, and (in) direct effect and effectiveness. In addition, the participation of national courts in the process of a dialogue with the Court of Justice of the European Union through the preliminary ruling procedure is captured. The analysis is not aimed at being exhaustive and focuses solely on the total impact of EU law on the national judiciary and the general trends in the judicial application of EU law, that is to say the overall reception of EU law and the dimension of the EU-friendliness displayed by Polish administrative courts.