Cyber-security can be defined as the protection of computer systems and mobile devices from theft and damage to their hardware, software or information, as well as from disruption or misdirection of the services they provide. Cyber-crime and cyber-attacks have become a growing threat to governments, businesses and individuals as digital technologies advance. There have also been allegations of cyber-espionage, proliferation of fake news and misuse of social media in some electoral campaigns. The European Commission updated the European Union’s cyber-security strategy in September 2017, to promote cyber-resilience and joint response across the bloc. This note offers links to reports and commentaries from some major international think-tanks and research institutes on cyber-security and relations issues. More reports on the topic can be found in a previous edition of ‘What Think Tanks are thinking’, published in February 2017.