The purpose of this study is to explore how the role of the public librarian can be seen in terms of social interactions with visitors, how they relate to trust and how it interacts with social capital. There is a trust in libraries that can contribute to social capital in society, but for public librarians, the complex social function that takes an increasing role in library activities can constitute a great responsibility and involve challenges on the individual level. In the discussion about trust in public libraries, it is therefore important to study the librarian’s perspective to highlight aspects that might otherwise not be visible in a Swedish context, which more often examines user perspective or the level of trust in libraries in society at large. This study takes an explorative approach on the social role in public librarianship, investigating the possibilities and difficulties concerning trust. Semi-structured interviews have been conducted to collect statements from six librarians at various public libraries. This study uses symbolic interactionism as a theoretical tool to understand librarians as individuals in their professional practice, and to create an increased understanding of their experiences. The results show that the social function is both complex and has a significant role for the participants. The work around safeguarding trust is about helping people and being accessible in different ways. The participants must be creative in their professional role as the social challenges can look very different based on different situations.