This week the mayor of Rotterdam, Ahmed Aboutaleb, will take part in the international conference on countering violent extremism in the White House. According to the US, well-informed, resilient local communities play a crucial role in this. The mayors of Boston, Los Angeles, Minneapolis and Saint Paul, Paris, Rotterdam and Vilvoorde (Belgium) have been invited to the summit. They will share their knowledge and experience with regard to preventing and tackling radicalism in their cities, as well as the way they deal with the influence international conflicts have on societies.