Given the proliferation of violent extremist content online in recent years, developing effective counter-narratives – messages that offer a positive alternative to extremist propaganda, or deconstruct or delegitimise extremist narratives and challenge extremist ideologies – is an increasingly necessary alternative to online censorship. This Handbook, funded by Public Safety Canada through the Kanishka Project, was created by the Institute for Strategic Dialogue (ISD) to help anyone looking to proactively respond to extremist propaganda with counter-narrative campaigns, and is intended as a beginner’s guide for those with little or no previous experience of counter-narrative campaigning. It takes readers through the main stages of creating, launching and evaluating an effective c ounter-narrative c ampaign. I t c an a lso b e u sed a longside I SD’s freely available online Counter-narrative Toolkit, which can be found at www.counternarratives.org. Our advice is based on ISD’s experiences in creating, running and evaluating in-house campaigns such as Extreme Dialogue, and collaborating with independent content-creators, from civil society and NGO campaigners to young activists, to amplify their counter-narrative messages through training, networking and campaign support. This Handbook therefore focuses on civil-society, youth or NGO-led online counternarrative campaigns.