Dr.-Ing. Lars Stein started his professional career in 1990 as a staff scientist at the Welding and Joining Institute (ISF) at the RWTH Aachen University in Germany. In 1996, he received his PhD in mechanical engineering. After some time in industry, he returned to the Welding and Joining Institute at the RWTH Aachen University in 2001 as an assistant to the directorate. Since 2003, he has worked as a senior engineer at the institute and, since 2007, he has been the head of the arc welding department.