I am curious, elina, do you have a US passport?
I live in Europe, with a US passport, and mine is stamped every time (except CH).

A friend with a Swiss passport never has it stamped. They will not stamp it even if she requests it.

No, Queenie, no US passport, I am Finnish.

My last trip to Europe was in 2000, so things may have chnaged - but I have tons of stamps on my passport - yes if you travel by tarin between two countries - they do not stamp the passport, however you can go to the police station and get a stamp - which we did out of sheer paranoia.
Agree with flannerUK better to be safe than sorry. You can get a one year multiple entry visa- and if you son does change his mind and decide to stay longer he can do so without worrying.

I did call the Netherlands Consulate in Los Angeles for more info. Once I got past the voice mail, the man I spoke with was very helpful, friendly, and spoke impecabble english. So that was a good start!

-- son may spend a grand total of 90 days in Schengen countries in a 6 month period, and no visas will be required (knew that).

-- Schengen countries (for visa purposes) should be considered like the states in the USA. One could spend all 90 days in France, or 6 days apiece in each of the 15 Schengen countries. But the grand total cannot exceed 90 days.

-- to be granted tourist visa for more than 90 days requires one of these 3 conditions:
1) student in a schengen country university. Eg, an official "student abroad" program.
2) visiting family members.
3) forgot the 3rd categeory, but *think* it had to do with your spouse being a schengen country citizen.
#1-3 have quite high burdens of proof and documentation.

-- none of #1-3 apply to my son: he just wanted to be a tourist for 4-5 month period.

-- Since #1-3 don't apply, son would require a "residence permit" (!) which would be very difficult to acquire and probably not worth the enormous hassle.

Based on this, what I'm going to advise my son to do is:

-- UK allows US citizens up to 6 months without visas (I confirmed at UK embassy web site). Spend a month or so there, which I think he's especially keen on, anyway.
-- spend a month in the non-Schengen eastern european countries he wants to visit (Hungary, Czech republic, Macedonia).
-- That leaves up to 90 days in the Schngen countries he wanted to visit, mainly France, Spain, Italy, possibly Belgium and/or Netherlands.
-- Switzerland, should he decide to visit, is NOT schengen country. US citizens may stay up to 90 days without visa, and it is completely separate of Schengen country rules.
-- Ireland, if he visits, is also completely separate from UK and schengen rules, so that's another 90 days.

So with some minor adjustments in itinerary, my son can skip all this visa stuff.

Thanks for taking the time to report back!

It's probably important to prepare some documentation for the immigration authorities in case he's questioned -- at the very minimum, get a return ticket and some documentation that he doesn't intend to stay in Schengen regions for more than 90 days.

That's what I'd do, anyway. I'm sure that he'll have a great trip!

By the way, this doesn't relate to your son's situation, but though Switzerland isn't a Schengen state, there're cases when it will take a Schengen visa for short stays depending on the nationality of the passport holder. In other words, in certain cases, someone who has a Schengen visa can go to Switzerland without the need for a Swiss visa.

But it's completely irrelevant here for your son.

this has been one of the most informative threads.. thanks to your perseverance, and a very helpful consulate employee.

hope he has a great trip. sounds wonderful.