IO Theater

iO, or iO Chicago, (formerly known as "ImprovOlympic") is an improv theater and training center in central Chicago, with a branch in Los Angeles called iO West. The theater both teaches and hosts performances of improvisational comedy. It was founded in 1981 by the late Del Close and Charna Halpern. The theater has many notable alumni, including Amy Poehler and Stephen Colbert.

Located at 1501 N. Kingsbury in Chicago, Illinois (formerly 3541 N. Clark St.), iO concentrates on "long-form" improvisational structures, in contrast to the "short-form" or "improv game" format of Theatresports, ComedySportz or the television show . The iO's signature piece is the "Harold", and the theater features other forms of improvisation, as well as sketch comedy and stand-up comedy.

In addition to five performance spaces, the building also has multiple classrooms for use by the theater's training center, as well as a large private event space. A large full bar is located on the first floor, a smaller one is located upstairs, and food is available from the kitchen downstairs.

The building has four performance spaces:

There are performances both upstairs and downstairs every night of the week, with the exception of some holidays. Shows can consist of either a Harold or a "show". Shows can be special limited runs (typically 1– 2 months) of a particular group / piece, or they can be open runs of long-standing formats using regular performers at the theater (e.g. The Armando Diaz Theatrical Experience and Hootenanny, which has the same format but a different cast every week). A typical Harold performance consists of two or three groups doing a Harold. Newer teams usually open the night and more veteran teams give the final performance(s). On some nights, usually in the downstairs theater, the groups play the short-form game "The Dream" using an audience volunteer after the second Harold of the night, and then play the short-form game "Freeze" after the final Harold. A show slot typically, but not always, has a Harold team open for them, usually one of the newer teams.

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