Optima Center, 200 E Illinois in Streeterville, has risen to two stories above the upper-level of Illinois Street. When complete the 325-unit building will be 42 stories tall.

The building in the background at the right of the photo is the new Ronald McDonald House.

Optima Center is a project that generates a lot of interest among architecture buffs, and you can see many more pictures of its progress in a thread at SkyscraperPage.com.

You can track the major new apartment projects underway in downtown Chicago at our at-a-glance list and map.