This Study Group is analyzing international law relevant to potential terrorist use of cyber attacks. Cybersecurity policy documents and analyses identify cyber terrorism as a serious threat, with governments fearful terrorists will use cyber attacks against critical infrastructure to damage economies and terrorize societies. The Study Group has four main objectives: (1) examine the threat of cyber terrorism and how technological trends and innovations might affect it; (2) define cyber terrorism based on relevant international law and state practice; (3) produce and analyze an inventory of international law relevant to preventing, protecting against, and responding to cyber terrorism; and (4) assess whether pro-active international legal actions on potential acts of cyber terrorism would be worthwhile and feasible.