The use of the Internet, particularly social media, by violent extremists and terrorists and their supporters received an increasing amount of attention from policymakers, media, Internet companies, and civil society organisations in 2017. In addition to politicians stepping-up their rhetoric regarding the threat posed by consumption of and networking around violent extremist and terrorist online content, prominent and heavily trafficked social media platforms also took a stronger stand on the issue this year, which caused civil liberties organisations considerable disquiet. This report treats developments in the violent extremist and terrorist online scene(s) and responses to them in the 12-month period from 1 December 2016 to 30 November 2017.