This policy brief examines how trade unions can use YouTube videos as a tool for organising and informing trade unionists and workers. Although often expensive to produce, YouTube content offers an effective way for trade unions to reach out to young people who are less likely to be union members. The briefing provides a cross country analysis of YouTube usage by unions, and case studies of successful campaigns using the medium. The authors distinguish two types of video: those that mobilise for protest actions, and videos that inform the audience about issues important to unions and their activities, such as wages or working conditions. They caution that ‘inward-looking’ videos, although important for galvanising supporters, are less effective in winning new members for unions in what is a very crowded market for viewer’s attention. Used efficiently, YouTube can nevertheless serve to raise awareness among the public about unions and what they stand for.