When Karl-Wilhelm Hausser joined the institute as founding director in 1929, his wife Isolde became a scientific assistant in his department and led a small group, working on ultrashort waves and vacuum tubes. When her husband died in 1934, she continued this work and also his studies on the effects of UV radiation on skin. In 1938, with the support of Richard Kuhn and of Krehl before he died in 1937, she became a Scientific Member of the KW society, only the third woman to achieve this status. She was able to form an independent department, if only with the title “Abt. Hausser”, with an independent budget. She also studied the effects of radiation on tumours.