Just received my entry permit over email from HR at the company I am heading to. But:

(The applicant has instructed the foreigner to obtain the entry visa from the Swiss representation mentioned. This authorization copy does not entitle you to cross the border.)

I'm expecting further instruction from HR at some point. But does this mean I will have to actually travel to the consulate or...? It'd be a short flight for me, but wasn't something I had imagined having to do. I haven't done this before so am completely ignorant of the process.

Yes, you have to pick it up as the visa will have to be in your passport

Yowzas! Okay, I guess I'll be making a pit-stop in SF then. Thanks @roegner

From the US, you can often send your passport to the consulate instead of going in person. The best way is to e-mail the consulate - they were super helpful to me for these sorts of questions.

Get your passport to consulate/embassy (As beltim check with consulate/embassy if you have to go in person or if you can send in the passport).
Then you will get a Visa D in your passport.
This allows to travel into Switzerland as an immigrant. This has to be done within the validity period of the visa.
Once in Switzerland you must register at the office of your commune where you live. This must be done within 14 days of taking up residency (Do not forget it when you move within Switzerland).
You should get than get a confirmation of residency from your commune. If not ask for one as this helps to open bank accounts etc. (Wohnsitzbestätigung or Anmeldebestätigung).
Finally you will get some when later your residency permit card. This card will act as a visa for future returns and also acts as a visa when you visit other Schengen member countries https://en.wikipedia.org/wiki/Schengen_Area .
You can stay in Schengen countries for up to 90 days in any given 180 day period as a tourist (except your country has a better bilateral treaty with the visiting country, like the US or Israel has with Germany).
For other countries which are not part of Schengen you will have to check what for your nationality applies (specially if you fly via UK. Less of an issue for US nationals than many others).

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The letter is just notification that your application has been approved. As others have mentioned, you need to go and pick up your visa.

After you are in CH, you have to go to the migration office to declare yourself, get fingerprinted and wait for your permit card.

Here is the relevant info from the Eidgenössisches Departement für auswärtige Angelegenheiten (EDA) / Federal Department of Foreign Affairs (FDFA). This is a little hard to find by searching so I am including the link below.

For the case of a work visa it will likely fall under the "Authorized Visa" category, meaning that your employer in Switzerland has applied to the consulate on your behalf, and an authorization for entry permit has been granted. As @klausenhauser points out, you will then need a copy of that authorization to send (or bring in person) to the consulate yourself.

https://www.eda.admin.ch/countries/u...ized-visa.html

The information at this link matches an email response I got from the consulate (except in the email they say 2 passport photos, and the link to photo requirements was broken...).

The wording of the first paragraph there is confusing and led me to fill out a visa application form unnecessarily (this one: https://www.sem.admin.ch/dam/data/se...sumd-en-de.pdf). I don't know why your employer/school/family member would apply on your behalf to the authorities in Switzerland, if you are just going to need to turn around and apply again at your local consulate. And indeed in my case, my employer did not do such a thing; they asked me which regional consulate in the US they should go to. So as far as I understand I just need to send the listed materials-- there is no additional paperwork to fill out.

Look to the above link for the things to include in the mail. The email I received from them said 2 passport photos as opposed to just one in the above link, so I will send two.

I'm going to include a cover letter to make it clear which scenario I am in, which lists the included documents so they know nothing is missing. Also I think it makes sense to put "ATTN: Visa Desk" in the address, but they don't ask for that anywhere on the website that I can see, and they didn't mention it in their email reply.