John's research focuses on 18th-century British art and visual culture, with particular emphasis on Joshua Reynolds and Thomas Gainsborough. He is especially interested in experimentations with artistic genre and media in this period of rapid social change, colonial expansion, and commercial growth; and the relationship between art practice, theory and the market. Within the collaborative environment of museums, his research in this area has deeply intersected with the material and technical study of paintings, often in dialogue with conservation.
Having worked for the National Trust for over a decade, a central strand of John's research has explored how art operates within the historic house, examining histories of collecting, display, and interpretation, and the ways in which works of art acquire meaning in domestic and heritage contexts.
A growing area of interest is in the homes of collectors of contemporary art in 20th-century Britain, and the transition of private collections of modern art into the national heritage. He was co-investigator on a project on this topic 'Representation, Resistence, Exchange' in 2022/23 funded by the John Fell Fund (Oxford University of Oxford Press).