I'm working on a project here in the U.S.

I want to interview someone on camera in Canada to use in the project.
Do I need any kind of work permit, etc? Permission?

Just trying to dot all my "i" s

Customs has a form, you can put your gear on there (include model and serial numbers) and get it stamped when going across - A quick google search did not reveal the form I am thinking of, but it's out there. When you come back, you will need to have the form checked so you don't have to pay tax on your gear as if you'd purchased it new.

You need foreign auto insurance.

You may need to arrange foreign tax. I've never done this, and can't give advice on it.

Hi Robert
I'm in Canada and live a few miles from a border crossing. Would try to get written permission first, especially if you're having to travel a long way. Not sure what is needed to make it "official". The border agents on both sides have a lot of discretionary power. If you show up with a reasonable story and a letter from the person you're intending to interview, they might let you through — but then again they might send you home. How far from the border does the person live? Could they meet you on the U.S. side? Also, bringing commercial gear across the border might need a carnet, rather than just a personal belongings declaration form.
Here's a contact link to our Canadian border agency: Contact Us (http://www.cbsa-asfc.gc.ca/contact/)
Good luck.

I do know that getting a visa to work just a few events in the US is a total P in the A. Sponsorship from somebody in the US, then an interview at the US Embassy in London, to explain why an American person could not do the job, rather than me, and then if granted, the times and dates are fixed. If the US do this to UK citizens, then I'd guess that doing a short job in Canada officially is going to be less than simple!