Abstract
The European Union is quite efficient in its efforts to protect fundamental rights to privacy and to personal data protection. even during the time of rapid development of communication technologies. Whether it is the European legislator or the EU Court of Justice, the overall approach reflects the todays' modernity.
Nonetheless, there have been certain confusion regarding the data retention of personal data by telecommunication services providers for the purpose of transferring the data to the public authorities since the declaration of Data Retention Directive invalid. The aim of this paper is not only to evaluate the effectiveness of European Union's practice within the evolution of new technologies regarding the challenges towards the right to privacy and personal data protection, but also to answer the question of whether we now have clear guidelines for data retention legislation on the national level.