This thesis examines the subject of reference interviews and the ways librarians form an opinion of users information needs. Using literature and interviews with three librarians I look at the questions below: - Why and when are reference interviews needed? - What significance do they have? - What ideas exist about the performance of reference interviews? - Are there any differences in librarians views of the questions above compared to views in the literature? Results from literature studies and interviews show that reference interviews can be important when librarians try to find out more about users information needs. However its neither necessary nor possible to analyse all reference questions. Librarians therefore need to determine if a reference interview is needed or not. It seems to be some situations and circumstances when an interview often is needed. Analysing the results I found ideas about the performance of reference interviews and ways to learn this art. Different skills and techniques are mentioned which can be used as tools during an interview and help the librarian to analyse reference questions. Librarians are important in reference situations and there are some characteristics which can be needed in them. Comparing literature with answers from interviews, I found both similarities and differences concerning the questions in the thesis.