The aim of this masters thesis is to examine how the educational work of the Swedish public library was regarded in the Swedish library journal Biblioteksbladet at three different periods of the twentieth century, i.e. the thirties, the sixties and the nineties. Using a theoretical framework from the field of professionalization and a methodological framework of hermeneutics, it is shown that the educational work of the thirties can be described as having a focus on free learning whereas the educational work of the sixties can be described as having a focus on public utility. The educational work of the nineties focuses on the information seeking process of the user. It is noted that this development during the century can be understood as a shift of the cognitive authority of the public librarians. It is shown that the change of exterior factors was discussed in two ways. The development of information technology has, in the eyes of the writers, moved the focus away from the collections of books to the use of tools for information seeking like the computer. The constant increase of adult students has gradually transformed the public library towards an education library. It is also shown that the public librarians had difficulties to welcome adult students. It is suggested by means of the theoretical concept of jurisdiction - that the reason for this is a conflict between the new role of the public library as an educational library and the older role that stressed free learning.