Method for joining fastening elements (12) such as studs on workpieces (14) such as metal sheets, said method having the steps of preparing a joining surface (18) of a fastening element (12) and/or a joining surface (22) of a workpiece (14) and of bringing the fastening element (12) and the workpiece (14) together in such a manner that the fastening element (12) is connected to the workpiece (14), wherein prior to the preparing step a cleaning step is carried out in order to clean the joining surface of the workpiece. Consequently, the cleaning step includes arranging a cleaning electrode (62) above the joining surface (22) of the workpiece and generating a cleaning arc (74) between the cleaning electrode (62) and the joining surface (22).