This paper describes joining of Advanced High Strength Steels (AHSS). Over the past 2 to 3 decades the usage of AHSS has increased constantly, and will continue. In order to succeed with the overall design it is of importance to know how to design AHSS from e.g. fatigue, bending and welding point of view. As presented in this paper, AHSS has to be treated differently than mild steel regarding welding.