In 1993, he became the director of the Max Planck Institute for Plasma Physics and was Chairman of the Plasma Physics Department of the European Physical Society between 1996 and 2004. In 1999, he became full professor at the Ernst Moritz Arndt University in Greifswald. From 2003 to 2005, he was head of the Wendelstein 7-X experiment. He retired in 2008.