It was at the Theresianum College in Wien in the 1770s when Ferenc Szechenyi, founder of the National Library of Hungary, as well as descendants of other library founder aristocratic families were taught about the librarian's professional responsibility by M. Denis, excellent professor of library sciences of that time. From 1845, all the Hungarian reference manuals related to library studies dealt with the question of professional conduct, and ethical requirements were laid down as well. The main theme of the Hungarian librarians' annual meeting in Eger in 1975 was the librarian profession and its ethical aspects. The keynote speech was given by the author of this article. The article evokes the professional debates before, during and after the meeting and formulates new ethical requirements arising from the digital age.