none.

So what are the best american young studios for you?

De Leon & Primmer Architecture Workshop (Louisville) is a good place to start the list.

Define 'young'.

"best" and "young" don't go together with "architect".

I don't know any European young firms. In Chicago Latent Design is rocking everything they touch right now. The work on Archinect's front page by BAM in Beijing is also pretty spectacular.

Note: These two firms could not be farther apart on the spectrum of contemporary practice, and I love this kind of diversity.

Are these young enough?

Kersten Geers 

Caruso St. John

Young for me is approximately under 40.

It is interesting for me to know and to compare young architecture studios.

It is also more interesting if everyone write one name of young studio of own country. In this way it is easier to know new architecture studio.

For me, for example, one of the best young european studio is Barozzi Veiga, also winner of Mies Van Der Rohe Award.

KGDVS is also a great studio for me, one friend works in their office in Bruxelles. Caruso St John is one of the more interesting studio in UK but they are older, they are over 50

I know there are many American students. For this reason the discussion can be more involved.

Andres Jaque