ASML’s product performance roadmap (overlay and throughput, image quality) requires ever more accurate and faster movements, more accurate and stable optical imaging capability. Low/no wear modules and parts are needed to maintain performance over the processing of millions of wafers at customers fabs.. Precision engineering involves applying the right design principles and selecting appropriate materials and manufacturing techniques to achiev this. In the presentation, an overview will be given of how precision engineering enables the ASML litho machines roadmap, what barriers there are and how we work on various breakthroughs looking into smarter mechatronics concepts, better materials and manufacturing techniques.