Changes in university staffing structures, the professionalisation of support staff and their increasing role in universities have been studied with varying perspectives and methods over the last two decades. The discussion has recently been enriched by the research conducted in different national settings. This paper contributes to the international debate and elaborates on the theme through two aims. The first is to investigate the emergence of a specific qualified professional group and its characteristics by analysing personnel data from Finnish universities. Second, the article seeks to indicate recent developments in the number and composition of professional staff in Finnish universities. The study is based on national official statistics on university personnel, some of which are previously unpublished, and on personnel data collected from all Finnish universities using an analytical framework built for this study. The results provide a comprehensive picture of the changing structure of the university workforce and a new insight into a previously studied occupational group through a lens of Finnish university system. The decline in the number of professional staff and the emergence of new kind of professionals in Finland reflect changes witnessed elsewhere, especially in Europe. Highly skilled professionals work in roles with specific knowledge, competences and responsibilities, which points out the differentiation of functions in the university system. This knowledge will support efforts to develop the university organisation by building on the competence of all staff.