Traditionally, the canon of Sherlock Holmes consists of the 56 short stories and four novels written by Sir Arthur Conan Doyle. In this context, the term "canon" is an attempt to distinguish between Doyle's original works and subsequent works by other authors using the same characters.
The traditional canon—usually capitalized by aficionados of the Sherlockian game as "the Canon"—consists of four novels and 56 short stories.
The description of these 60 adventures as the Sherlock Holmes canon and the game of applying the methods of "Higher Criticism" to it was started by Ronald Knox as a playful use of the traditional definition of Canon as an authoritative list of books accepted as Holy Scripture.
Here is the list of the four novels of the canon:
The 56 short stories are collected in five books:
Frequently, "The Adventure of …" is dropped from some story titles in current-day anthologies. However, in their original appearance in The Strand, this is how the titles were given in many cases.
Published 31 October 1892; contains 12 stories published in The Strand between July 1891 and June 1892 with original illustrations by Sidney Paget.
Contains 12 stories published in The Strand as further episodes of the Adventures between December 1892 and December 1893 with original illustrations by Sidney Paget. (After the magazine publication Conan Doyle included "The Adventure of the Cardboard Box" in His Last Bow only.)
Contains 13 stories published in The Strand between October 1903 and December 1904 with original illustrations by Sidney Paget.
Contains 7 stories published 1908–1917. (Early editions have 8 stories, including "The Adventure of the Cardboard Box" in this collection instead of in The Memoirs of Sherlock Holmes.)