The elementary interest of every country is to maintain its inner security and stability. To achieve this goal the state must restrict within legal frameworks some fundamental rights of its own citizens. One of these fundamental rights is the right to privacy that can be breached only under certain circumstances. It is easy to see that it is unacceptable for a state not to control within the legal frameworks the communication of its own citizens so they can commit crimes, run terrorist rings, or spy rings or establish drug cartels without any consequences. Of course, the control over the communication is not the only means of the successful investigation but undeniably a vital one. That is why the Janus faced nature of the Dark Web is a real security risk nowadays. Although this new medium is the fruit of the last two decades its presence today is stronger than ever before and its popularity is growing day by day. Its most important features are anonymity, hidden geolocation and freedom from censorship. The Dark Web is very useful when it provides anonymity for political dissidents and whistleblowers, but is very harmful when it provides the same features for arm and drug traffickers and terrorists not to mention for pedophiles and so on. This article aims to shed some light on the effects of the Dark Web on the security and economy of the states especially in the aspects of organized crime and the terrorism.