To address the concerns of simultaneously improving crash performance and fuel efficiency in the automotive industry, multi-material car bodies are becoming increasingly popular. Aluminium and steel are two materials whose properties complement each other well for this application. However, ultra-high strength steel (UHSS) and aluminium alloy is a hard-to-join material combination. In the last decades different solutions to this problem have been proposed, one of these being friction element welding (FEW). In this work, different UHSS have been joined to different aluminium alloys through the FEW equipment EJOWELD developed by EJOT. The joints have been evaluated though visual inspection, cross-section analysis, and mechanical tests. All materials could successfully be joined by the EJOWELD process.