The Unternehmen Reisebüro, also known as the Girrmann Group, was one of the first and most influential groups helping people escape from East Berlin during the Cold War. It was started by students at the of the Free University of West Berlin. The founders of the group were law students, and . Their original purpose was to help their fellow students, but the program later expanded to helping anybody who had hopes of escaping East Berlin. Together these two students managed to set up an evolving network that helped thousands of East Berliners safely escape.After they were banned from crossing on August 23, 1961, they used students with West Berlin or foreign passports to contact students in East Berlin and ask them if they wanted to escape.