The nationwide market for cannabis opened Wednesday at midnight amid lingering questions about the impact on health, the law and public safety.
Preparations included mailings to 15m households detailing the new cannabis laws and public awareness campaigns.
But there remain concerns, including about the readiness for police forces to tackle drug impaired driving.
Canadian provinces and municipalities have been preparing for months for the end of cannabis prohibition.
Provinces and territories are responsible for setting out many of the details for where cannabis can be bought and consumed within their jurisdictions.
This has created a patchwork of legislation across the country as jurisdictions choose more or less restrictive frameworks for selling and using cannabis.
Shops in the province of Newfoundland, the most easterly time zone in Canada, opened as midnight struck for the first legal sales of cannabis in the country.