The First Edition of Modern Canadian Doubled Die Varieties is a comprehensive catalogue written by John O'Connor, a numismatist from Kawartha Lakes Ontario. In late 2018 after conversing with like-minded experts and collectors regarding the lack of publications, research, or documentation for this type of die variety, John decided to take on the task of documenting, finding, and occasionally making new discoveries of doubled dies on Canadian coins intended for circulation and proof-like sets.

Inside the first edition, readers will find detailed images showing how these types of die varieties can occur during a process known as hubbing and explain how to tell the key differences between common forms of worthless doubling and genuine doubled die varieties. There are 57 listings and detailed price charts, mintage reports, compositions, weights, and over 100 colored images to use for comparison purposes while searching for these oftentimes scarce varieties.

Additionally, there is an extensive reference list containing 173 doubled die listings across all seven denominations of Canadian coins with some information cited from well-known collectors, experts, and websites that have given the author proper written permission to reference individual listings, listing numbers, websites, images, coin community forum posts, and written information so that collectors new and experienced can have access to presumably the largest Canadian doubled die reference list to date.