Because this subject pops up quite frequently in this sub-forum, I am re-posting information I found on a forum dealing with legal videography and court reporting. Specifically dealing with US court reporters and legal videographers trying to cross the border into Canada to take legal depositions, but it is my understanding that the same rules apply no matter the nature of work.

Canadian law seems somewhat complex on the subject, but there is a fairly simple description here: Canada Work Permit - Business Visitors (http://www.canadaworkpermit.com/businessvisitor.html#)!

If this still leaves you scratching your head, the same website offers a free analysis of your specific situation, all you have to do is either call their 800 number or fill out a web form in order to find out if you need a work permit. Canada Work Permit (http://canadaworkpermit.com/assess/#)!

I hope this will help someone...