I am not from Chicago and have only had an opportunity to visit a couple of times, always for work. As the person in the group who really loves food, though, I have been tasked with finding places to eat. The client is most interested in a relaxing and elegant atmosphere, and very good food. A boisterous setting would not work for these folks; they want to be able to have quiet conversations. They also love steak, but it isn't required. Price is not really important, but being able to get a reservation on short notice - for next week - is. We may also need to shift the reservation time if meetings run long during the day. So that said, I did some research and came up with Tesori, Primehouse and Naha as possibilities. The client also came up with a list from Zagat which included Rosebud Prime and the Palm. Any feedback would be greatly appreciated!
Edited to add that they will be staying near the theater district. Proximity to that area would be great because they will be pretty tired from work and travel.