The purpose of this master’s thesis is to study the organisational culture of two public libraries managed differently. One of the libraries in my study is run by the local bookstore and the other is run by a staff co-operative. My aim is to elucidate characteristic features in the culture of these two public library organisations. The questions I posed are which types of organisation culture can be identified in the two given examples and what the factors are that may be of importance for these cultures. In my study I use Henning Bang’s definition of organisational culture as a set of common norms, values and comprehensions of the reality formed in an organisation through cooperating within the group and with the outside world. I’ve also used Bang’s division of the concept into content and expression, when I’ve gathered information in my empiric study. The study has contained of texts from and about the chosen libraries, an inquiry answered by all the staff members and interviews with three members from each organisation. I have used Critical Values Framework and Organizational Culture Assessment Instrument as tools for analysing the material. Both libraries in this study can, according to these tools, be characterised as clan oriented. Although the similarities, the organisation culture in the two libraries differs in many ways. My conclusion is that the specific context of history and the driving force of change, are of great importance to the organisation culture.