First of all Juilen is a beautiful restaurant with it's crystal chandeliers and elegant furnishings. It's one of those restaurants where women do not know what to wear - I saw everything from sweaters to ball gowns. I would say a suit or cocktail dress would be a safe bet.
The service is very friendly and not at all stuffy which was a nice surprise. Also, in these type of restaurants the food tends to be (how shall I put this) a little stuffy as well. But, I am happy to report that it was not at all - I had smoked salmon and lobster (completely out of the shell) as an entree. It was wonderful. A perfect place for a special evening out.