Thanks to Gail Dever's article Toronto city directories digitized, 1910 – 1926 I learned that missing city directories for 1910, 1915, 1916, 1920, 1923, 1924, 1925 and 1926 have been digitized and are now searchable online.
The first Toronto directory was published in 1833. Most directories contain an alphabetical list of inhabitants (usually
heads of households and others working outside the home), and a list of
occupants arranged by street.
Genealogists with Toronto-based ancestors won't want to miss this set of city directories.