Our focus is the digital humanities, especially visualisation of datasets such as text archives and object collections data in museums. The name “digital humanities” implies just two disciplines, computing and the humanities. What is the designer’s role? Collectively we should be able to explain what our contribution is —especially when some may fear our replacement by AI systems. We argue that there are particular aspects of designing that are distinctive and can enable more effective visualisations to be produced: (1) expertise in the visual articulation of meaning, (2) human-centric methods, and (3) the quick and adaptable use of low-fidelity early prototyping. We base our argument especially on the idea of design as a form of inquiry or research, and illustrate the three benefits using our recent interactive data visualisations with organisations including the Wellcome Library, Cooper Hewitt Smithsonian Design Museum and V&A London.