Hate speech on the Internet is an increasing problem for society as a whole. According to a recent study, almost 80% of Internet users have already seen hate speech or hate comments on the Internet; among younger Internet users (14-24 years), the figure is as high as 96% (source: Landesanstalt für Medien NRW, 2018). To complement existing initiatives to regulate, monitor or report online hate speech, the EU project SELMA (Social and Emotional Learning for Mutual Awareness) takes a proactive approach: the two-year project aims to address the problem of online hate speech by promoting mutual understanding, tolerance and respect.