Fonds consists of materials documenting William Dendy's life and career as an architectural historian including university course notes, research material for published works, research material on the history of Canadian architecture and other research interests such as Forest Hill, Hamilton, the architects Frank Darling and William Somerville, and the Massey family. Some materials relate to Dendy's teaching activities, Toronto walking tours and consultancy projects.
Also present are articles, card files, clippings, correspondence, electronic records, ephemera, manuscripts, maps, manuscript and typescript notes, as well as photographs, negatives, and approximately 40,000 slides (including more than 17,000 images of Canadian architecture, urban space, and landscape). The slides were taken by Dendy and are each individually identified by him.