ABSTRACT This article reports on findings of an international scoping review of literature on social work in libraries. The review explored how social work is practised in libraries, and barriers and facilitators to embedding professional social work within public libraries. Using a literature search protocol, databases were systematically searched, and results refined through several phases of data screening, resulting in 16 articles eligible for inclusion. The dataset was thematically analysed by the research team. Data analysis revealed that most articles emanate from research undertaken in metropolitan settings in the United States, and that empirical research has typically been small-scale, using qualitative or mixed methods. Most articles described social work as multidimensional, including direct contact roles with library visitors, as well as indirect practice with library staff for professional development purposes. In the dataset, authors acknowledged the changing role of libraries that sees a greater focus on addressing social justice issues with increasingly diverse populations of library visitors and their evolving needs – a focus in common with social workers’ practice. Authors identified opportunities and challenges regarding interprofessional collaboration between social workers and library staff, including role boundaries and sustainability. Building on these themes, implications for future research and interprofessional practice are discussed.