The standard paradigm when securing networks is to filter ingress traffic to the domain to be protected. Even though many tools and techniques have been developed and employed over the recent years for this purpose, we are still far from having secure networks. In this work, we propose a paradigm shift on the way we secure networks, by investigating whether it would not be efficient to filter egress traffic as well. The main benefit of this approach is the possibility to mitigate malicious activities before they reach the Internet. To evaluate our proposal, we have developed a prototype and conducted experiments using NetFlow data from the University of Twente.