The LaserSeamStepper (laser welding gun), introduced by IPG, is a new laser welding tool which is comparable with a standard resistance spot welding gun. The components are initially pressed together and then welded by laser radiation. The integrated laser safety function greatly facilitates the use of the laser material processing and keeps down high investment costs. Manual guided laser welding and one-sided accessibility extends the range of applications and manufacturing processes. Overlap joints in the automotive industry (car body) as well as planking of space frame structures can be done very cost-effectively on a normal shop floor. A continuous improvement process has taken place since the beginning of car series production with the LSS, the result of close cooperation with different car manufacturers. This results in a highly reliable laser welding tool with an availability of 99.9 percent. Due to the high repeatability of the complete system (fiber laser and LSS module), a very high continuous production quality can be guaranteed without any rework at the manufactured part itself.