Cyber security has become a focal point for conflicting domestic and international interests, and increasingly for the projection of state power. The military utility of the cyber domain is linked to the economic and social potential of information and communications technologies (ICTs), while technologies with military and national-security applications have become essential to the conduct of modern life.In light of this, Evolution of the Cyber Domain provides a holistic review of the strategic, operational and technical issues at the centre of the international cyber-security debate. The Dossier charts and contextualises the key developments and trends that have shaped the cyber domain since the 1950s. As well as tracking the events and decisions underlying the military potential of ICTs, it examines the issues and policies that affect global governance of the internet.The Dossier analyses:• The geopolitics of international cyber security and technological development.• The challenges of creating methods for managing conflict within the cyber domain based on international law.• The tension between issues of privacy, freedom of information and national security.• Intelligence as a state practice in peace and war.• The development and use of cyber military capabilities.The Dossier is an important point of reference for further research and analysis on complex cyber-security issues, and it provides a series of insights into national positions, as well as regional and global agreements and policies. Evolution of the Cyber Domain is a useful resource for readers who seek a comprehensive picture of cyber affairs, and who wish to understand the social, economic and politico-military challenges that have guided the development and use of ICTs in the past six decades. By summarising the ways in which governments are addressing these challenges at the strategic level, it helps prepare decision-makers and researchers involved in the formulation of cyber-security policy, strategy and analysis. The Dossier also contains a glossary of the key terms and concepts in the cyber-security dialogue.