You do not have to give up your citizenship if you apply to become a citizen of Canada. However, a person who wishes to keep their current citizenship and also become a Canadian citizen must carefully read the laws of their existing citizenship. In some instances a person's citizenship may be revoked when they gain citizenship to another country.

Gaining Canadian citizenship often does not revoke a person's legal duties to the other countries they hold citizenship with. For example, if a country has mandatory military duties, that person could be forced to fulfill their duty, or imprisoned for not fulfilling their commitment at a specified age. You may also be required to pay taxes even though you have not been living in that country.

Many international parental child abductions involve parents and children who are dual citizens. Officials of the government of the country where the parent and/or child is a dual citizen will determine whether or not to issue the child a passport or visa. If you are worried about your child being abducted, you or your lawyer can ask the foreign government not to issue these documents. However, the foreign government may not comply.

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