Sail Canada's Racing Rules of Sailing for 2021-2024 includes Sail Canada Prescriptions and incorporates changes and corrections approved by World Sailing as of 1 January 2021. The Racing Rules of Sailing includes two main sections. The first, Parts 1-7, contains rules that affect all competitors. The second, Appendices A-T, provides details of rules, rules that apply to particular kinds of racing, and rules that affect only a small number of competitors or Officials. The racing rules are revised and published every four years by World Sailing, the international authority for the sport. This edition became effective on 1 January 2021. Marginal markings indicate important changes to Parts 1-7 and the Definitions of the 2017-2020 edition. No changes are contemplated before 2024, but any changes determined to be urgent before then will be announced through national authorities and posted on the World Sailing website (www.sailing.org). Sail Canada Appendices U & V are available at sailing.ca/rules-prescriptions.