What if someone else wants to use my mark in Canada?

"You name it!"

It is possible to permit someone else to use your mark so long as that other person is properly licensed to do so. The owner of the trade-mark must retain direct or indirect control of the character or quality of the wares or services thta will be used or performed in association with the trade-mark that is licensed.

It is not madatory that any licence be in writing. However as a practical matter of organizational control as well as legal matter of proof, most trade-mark owners will want licences to be in writing.