The aim of this thesis is to examine how librarians and family historians experience their interaction at the reference encounter, what influences these views and how they affect the service; whether the family historians are aware of these views; which subject knowledge is needed and how this knowledge affects work performance; if there is a need for continuing education, and finally, if the family historians themselves can work as a resource for the library or the librarians? The thesis consists of three parts; in the first a theoretical frame was constructed around the concepts service, continuing education, subject knowledge and attitudes. Role theory was used as a theoretical background to show how expectations influence professional roles. The second part consists of the results given from the qualitative interviews with librarians and surveys with family historians that were performed. In the last part a discussion from the theoretical and empirical information earlier received was made. According to the family historians the service given from librarians is good but a change in knowledge is needed. Although appreciated by the family historians the librarians of ten have a negative view of them, probably caused by insecurity as a result of lack of knowledge. Continuing education and instructions from family historians and subject specialists can help to change this.