Architectural historian. He is Fellow of Kellogg College, University of Oxford and his main academic interests are in British and European architectural history, especially from the 18th–20th century, and the history of urban planning since the Renaissance. His books include John Nash: Architect of the Picturesque. He was co-editor of the revised volume on Berkshire in the Pevsner Buildings of England series, and is currently co-editing a book on the Victorian architect Sir George Gilbert Scott. He is also Editor of the Georgian Group Journal.