Canada - Passport & Nationality - Dual Nationality
Since 1977, Canada has permitted its citizens to hold dual or multi Citizenship. As a result, Canadian citizens will not lose their Canadian Citizenship if they retain their former nationality or become citizens of another country.
If you intend to become a Canadian citizen, you are advised to verify whether the country of your current nationality permits dual citizenship. For more specific information about some countries where you hold citizenship:
Under the nationality laws of some countries, a married person automatically has his or her partner's nationality. Children may also have a parent's nationality even if they were born abroad. If your wife, husband or child is visiting the country of your nationality, you should check with the country's consulate or high commission in the United Kingdom before you travel.