The essence behind terrorism is to instill fear in citizens so they demand changes from their governments, which will be beneficial to terrorists and their aims. The highest impact of terrorist activities is obtained if they are targeting state citizens or infrastructure. The chapter notes cyberspace and terrorism interactions in three ways: (i) cyberspace can be a facilitator – used as a communication tool or recruiting tool to perform a “classical” terrorist act; (ii) cyberspace as an instrument – assuring performing the terrorist act either by providing access to targets or to conduct information warfare; (iii) cyberspace itself can be the target of the terrorist act – aiming to disrupt its operations or access to it or to pollute information or services and create users' distrust. Some state measurements for counter terrorism before, during and after their activities are further marked. Obstacles, problems and the high significance of this process are finally discussed for the state from social, legal and technical perspectives.