This timely Research Handbook contains an analysis by leading scholars and practitioners of various legal questions concerning cyberspace and cyber activities. Comprehensive and thorough, it succeeds in mapping out the range of international rules that apply to cyberspace and to specific cyber activities, assesses their regulatory efficacy and offers insightful suggestions, where necessary, for revised standards. Contributors examine the application of fundamental international law principles to cyberspace such as the principle of sovereignty, jurisdiction, state responsibility, individual criminal responsibility, human rights and intellectual property rights. They explore the application of international rules to cyber terrorism, cyber espionage, cyber crime, cyber attacks and to cyber war. They deal with the meaning of cyber operations, the ethics of cyber operations as well as with cyber deterrence. Finally, they comment on the cyber security policies of international and regional institutions such as those of the United Nations, the European Union, NATO and of Asian-Pacific institutions. This Research Handbook will benefit scholars in the fields of international law, international relations, public and private law. Researchers will find the suggested future research avenues in this field invaluable whilst policy-makers and practitioners will gain fresh insights into topical issues concerning the regulation of cyberspace and of cyber activities.