The number of investors actively participating in the financial markets is steadily rising. There is also an increase of the services and facilities offered by licensed investment firms and banks that have received the respective licence. These parameters, as well as the weaknesses highlighted by the financial crisis in terms of the operation and transparency of the markets for financial instruments, have led to the need to re-modify the current European institutional framework. The modifications create a harmonized set of regulations and offers investors a high level of protection, taking into account the nature, scale and complexity of the investment services.