Since 1999 the European Union has intensified its efforts to finalize the creation of a single financial market. The determination of EU in this respect was reflected by the creation of important documents: the Financial Services Action Plan (FSAP) and the report of the Committee of Wise Men. FSAP contributed to the creation of legal foundations, thanks to which such a single market may come into existence. The reports of the Committee of Wise Men contributed on their part to the reform of the law making procedure with respect to financial markets. At the first stage of market building, in the years 1999-2005, solid legal foundations were created, constituting a good starting point for a closer integration. The process of market building is now entering its second stage. The newly adopted legal acts must be introduced into the national legal systems of the EU Member States and their provisions must be applied in practice. The main task now is to ensure the proper functioning of the single financial market, which involves, i.e. an ongoing monitoring of the introduction and application of the law in force. These matters are raised in the Green Book prepared by the European Commission, which contains proposals of actions concerning the European financial market in 2005-2010. The conclusions from the discussion on the material contained in the Green Book will feed into the White Book due to be published in November 2005 with the final version of the programme of actions scheduled for the second stage in 2005-2010. As it was pointed out earlier, the supervision of the application of adopted legal acts is likely to be the main EU objective at this stage. However, the EU has to address one more important problem: determining what is the desired scope of integration of the Member States` financial markets. In other words, what is the real, as opposed to ideal, state of affairs, which the EU can accept in order to be able to conclude that its actions towards the building of a single financial market have been successfully accomplished?