Every week is restaurant week as far as we're concerned, but Chicago's Restaurant Week is a great opportunity to try some of the best restaurants in town on a budget, when they offer prix fixe menus that make it easier to give them a try. (The standard deals are $22 for lunch, and either $33 or $44 for dinner, excluding beverages, tax and tip.) This Restaurant Week, the fifth, will be February 17 through 26 (which is, you will note, more than a 7-day week; it includes weekends at both ends) and over 200 restaurants are participating this year. Many of the most popular tickets go quickly— specifically, Blackbird and Naha, as soon as Phil Vettel writes his annual preview article in the Trib recommending both of them— but that just leaves 198+ other places to check out, from Adobo Grill to Yoshi Cafe. This tool has the complete list along with details on what they're offering; you can make reservations directly from it.
And if you can't wait that long, you can attend the First Bites Bash on February 2, which isn't bargain-priced (tickets are $125) but is a very good thing, since 100% of the proceeds will benefit the Greater Chicago Food Depository. Stephanie Izard will be the hosting chef, with dozens of others participating. Those tickets are available here.