The aim of this thesis is to examine how two young adult departments at two public libraries work and what profiles the young adult departments have. To examine the work and profiles at the young adult departments I have used the following questions: What are the ideas about working with young adults? How are the two departments in this study working whit young adults? What or which are the profiles of the young adult departments in this study?To answer the questions above I used a qualitative method based on interviews with the librarians responsible for the young adult departments. To complete the interviews I studied the libraries Internet sites and official documents. The examined departments are located at two city libraries and were chosen manly for their focused age group, 15-25 years and that the departments are well established.To analyse the results I used the theoretic model of Marianne Andersson and Dorte Skot-Hansen about the role of the public library. The model describes library profiles from four perspectives: the library as a cultural centre, a knowledge centre, an information centre and a social centre. I also used previous studies about the work with young adults at public libraries to analyse the results from the empiric studies.The analytical findings show many similarities in young adult services between theory and my study. Marketing, user treatment, user influence, the selection of activities and media and finally co-operation are the five categories in which the libraries focus their work with young adults. This is according to the results from my study and previous studies. The results from the analysis of the departments profiles show that the departments have traces from three of the categories but the main profile of both departments are the departments as a cultural centre.