After the German reunification, the university was radically restructured under the Structure and Appointment Commissions, which were presided by West German professors. For departments on social sciences and humanities, the faculty was subjected to a "liquidation" process, in which contracts of employees were terminated and positions were made open to new academics, mainly West Germans. Older professors were offered early retirement. The East German higher education system included a much larger number of permanent assistant professors, lecturers and other middle level academic positions. After reunification, these positions were abolished or converted to temporary posts for consistency with the West German system. As a result, only 10% of the mid-level academics in Humboldt University still had a position in 1998. Through the transformations, the university's research and exchange links with Eastern European institutions were maintained and stabilized.