The aim of this paper is to examine the scope of some rights stemming from the possession of European Union' citizenship. Although the rights resulting from this citizenship are commonly known, their exact extent is precised in the European Court of Justice's (ECJ) jurisprudence in a way that often broadens the literal interpretation of Treaty provisions. This generally positive process is sometimes contrary to the Member States' economic interests. In the paper, the analysis of recent jurisprudence of ECJ concerning this problem is divided into two parts. First the relationship between citizenship and the prohibition of discrimination based on nationality (art. 12 TCE) is considered. The ECJ insists on verifying in each case if the situation is a purely internal situation, refusing in such circumstances the application of Treaty provisions on citizenship. But the definition of 'transnational factor' is so broad that it hardly happens. Thus the generał prohibition of discrimination based on nationality is regularly used by the ECJ in cases concerning EU citizens. Second, the limits for applying the right of circulation and stay (art. 18 TCE) are examined. The Treaty imposes an obligation to consider secondary legislation as setting those limits. The Court however generally ignores this indication and interprets the Treaty provisions as if no secondary legislation was in place. Further in the paper, this recent jurisprudence is confronted with the provisions of directive 38/2004 on rights of EU citizens. The directive solves most of the doubts raised by the judicial decisions of the ECJ, limiting the scope of rights set by the Court. The analyzed jurisprudence indicates that the ECJ is determined to grant as broad the rights to the European citizens as possible, sometimes against the will of particular Member States. If the attitude of the Court remains as it is presented in this review of jurisprudence, the clear limits granted by the directive 38/2004 might be overlooked in the further Court's activity.