Hi
I have to travel to my US head office for 3 days as an orientation. As a permanent resident with a British passport, what visa do I need and where do I get it?

Thanks!!

Until you have Canadian citizenship, you'll need to approach things like this as a UK citizen. If you are flying to the US, you'll need to make sure you have ESTA:

https://esta.cbp.dhs.gov/esta/

This costs $12, lasts for two years and is a Visa waver program for UK citizens (and other countries).

If you are traveling by land and driving across the border, you'll have to fill in a green form, pay $US6 (credit card or US dollars only) and they'll stick a little green visa stub in your passport which is valid for three months. If you're not planning on returning to the US within these three months, make sure you hand it back at the Canadian border. The Americans really don't like it when you keep it in there past expiry, I've made that mistake more times than I should have!

be careful at the border if questioned.
you are there to attend meetings not to WORK. (presuming this is the case of course).

If you are doing more than attend meetings then it may be the VWP is not appropriate. Maybe someone on the US boards would be able to help

i also suggest taking a letter from your HR basically stating that you are employed and paid by the Canadian company however will have to visit their US offices for training and business meetings.
The I94 waiver or ESTA is sufficient for these types of visits.

What are customs and immigration regulations for Canadians and travelers from Visa Waiver Program - eligible countries?

If you are from a visa waiver program country and you are coming for tourism or business (but not for employment or as a working member of the media) you may enter into the U.S. (including Hawaii, Alaska, Puerto Rico and the U.S. Virgin Islands) for up to 90 days. If you wish to visit the U.S. for a longer period of time, you will need to obtain a visa.
https://help.cbp.gov/app/answers/det...4/kw/b2%20visa