Easy access to firearms is a major driver of violence in Brazil. What responsibility do arms suppliers like Switzerland have? A new study by terre des hommes schweiz and terre des hommes Germany explores this question. It analyzes the extent of gun violence in Brazil and the role that armaments from Europe play in violent crime in Brazil. In addition, it reveals the background to the increasing lethal police violence and assesses the efficiency of state arms stock control. Recommendations are then provided for stronger regulation of Swiss arms exports to Brazil.