The IISH research group consists of around 10 senior researchers, added by a varying number of postdoc researchers and PhD students. In addition, the IISH receives Fellows, Honorary Fellows and Guest Researchers. All in all, the research group consists of 30-40 researchers.
Since 2014, the research group is been led by Professor Leo Lucassen, with Professor Karin Hofmeester as deputy. A number of senior researchers also have an appointment as professors at a university, usually for one day per week.