The financial crisis has emphasised the need to harmonise rules on the functioning of financial markets, a crucial source of financing in today´s economy. The EU actively tries to improve, in particular, the accountability of financial institutions and transparency of financial markets, at the same time combatting tax evasion and money laundering. These legitimate policies often require, in practice, the collection, use and storage of large amounts of personal information. Therefore, it is necessary to balance public policy objectives with the fundamental rights to privacy and data protection.