Markus Ernstberger successfully completed an apprenticeship as a mechanic in 1990 and continued his studies via a distant learning course leading to certified engineer status at the DAG Würzburg. He worked at the KIT’s (Karlsruhe Institute for Technology) Institute for Technical Physics as a technician for 11 years. In 2002 he was admitted as a civil servant to the European Commission’s Joint Research Centre, ITU, in Karlsruhe. Initially, Markus worked as an engineer for the Hot Cell Technology unit in the Thermal Analysis sector. In 2007 he started working with irradiated nuclear fuels, actinide compounds and other reactor materials for the Materials Research unit in the Electron Microscopy (SEM, EDAX, FIB, TEM) sector. The main focus of this work is on the operation of the Scanning Electron Microscope (SEM) and also the preparation of thin films for Transmission Electron Microscopy, as well as the conditioning and preparation of various samples suitable for the different types of analyses carried out in the electron microscopy laboratory and nuclear forensics investigations.