I'm from the SF Bay area and am going to be in Chicago for a week on business and the company paycheck for dinning, so money is not a problem. And one night we're going out for Italian and it's my job to find the restaurant and I've never been to Chicago before. Thanks.
Well, easily the best Italian restaurant in town is Spiaggia. It's one of the best restaurants of ANY kind in town. Tony Mantuano, the chef/partner, won the James Beard Award for Best Chef - Midwest in 2005. It's expensive and a dress-up place. The cuisine is divine. www.levyrestaurants.com
For more discussion about the many Italian restaurants in Chicago, see this discussion:
P.S. Be careful not to confuse Spiaggia with Cafe Spiaggia, its sister restaurant next door. Spiaggia is the expensive, dress-up place. Cafe Spiaggia is not as expensive and casual. Both are very good at what they do. You'll find sample menus for both, including prices, on the Levy Restaurants website (see link above).