The study's aim is to create an understanding for the question why Sweden in 1921 chose to create its own classification system for public libraries instead of adapting e.g. the Dewey-system which - at this time - was internationally we11 spread. It examines the social changes which proceeded the creation of the Swedish Library Association (SLA) in 1915 and discusses in depth the work of the committee appointed by SLA to create the classification system. Special interest is also given to the relation between SLACS and the Dewey-system. The study shows that the main influence on the codttee's work was the former Swedish tradition of classification practice. The Dewey-system was seen as inappropriate to adapt in the Swedish libraries because of the vast changes that would have to be done, and the fact that the decimal notation was practically unused in any libraries in Sweden. From a methodological point of view, the study tries to apply a critical hermeneutical approach as developed by Paul Ricoeur. The study contains an extended English summary.