Gaining a decisive technological edge is a never-ending pursuit for defense establishments and the countries they protect.Intensifying geo-strategic and geo-economic rivalry among major powers, especially the U.S. and China, and the global technology revolution occurring in the civilian and military domains promise to reshape the nature and distribution of global power. This book examines the state of global defense innovation in a select number of countries chosen because they are representative of the diverse make-up of the global defense innovation community.These include small countries with advanced defense innovation capabilities (Israel and Singapore), closed authoritarian powers (North Korea and Russia), large catch-up states (China and India), and advanced large powers (U.S.). The chapters in this book were originally published as a special issue of the Journal of Strategic Studies.