After the EU Enlargement of 2004, the law courts of the new Member States now fulfill a twofold role of applying both national and European law. The application of European law also entails the duty of judges to construe their own domestic law as close as possible with EU law, and, if that is not possible, the duty arises to set aside the domestic law found to be incompatible with European law. In consequence, developments in the next decade will test judges’ capacity for properly applying European law and this process will inevitably present a serious challenge to the Central European judicial systems. While evaluations can first be made no sooner than a few years after the EU Enlargement, there are important indications that can suggest the probable outcome of that challenge. This article briefly outlines the application of European law in those countries prior to EU Enlargement and then deals with the important factors which are likely to influence its future application in the new Member States.