The following requirements must be met by anyone who wishes to obtain a Canadian tourist visa before entering the country:

1. Proof of financial support: You must be able to prove that you have sufficient funds to support your stay while you are in Canada, without working or accessing social services.
2. A valid passport: The passport must be valid for at least 6 months after the planned day of departure.
3. Health insurance: You must have proof of valid health insurance to cover any medical related expenses during your stay in Canada.
4. Valid temporary resident visa: Depending on where you’re coming from, you may require a temporary resident visa as part of the visa application process.
5. Letter of Invitation: A letter of invitation is mandatory and must be filled out by the host already in Canada.
6. Additional Documents: Depending on the country you are from, other documentation may be required, such as a police certificate, letter of explanation, etc.

The Canadian tourist visa is generally valid for up to six months; however, the actual length of stay granted will be determined upon arrival at the Canadian port of entry. Those interested in obtaining a Canadian tourist visa must also take into consideration the fact that the visa processing time can take up to 45 days, depending on where the application is submitted from.