ImprovOlympic

The I.O., or I.O. Chicago, (formerly known as "ImprovOlympic") is a theater at 3541 N. Clark Street in the Wrigleyville neighborhood of Chicago, Illinois dedicated to improvisational comedy. It was founded in the 1980s by Del Close and Charna Halpern. The I.O. approaches improvisation as an art form in and of itself; this differs from the Second City approach, where improv is used as a tool in creating sketch comedy. I.O. also concentrates on "long-form" improvisational structures, in contrast to the "short-form" or "improv game" format of Theatresports or the television show Whose Line Is It Anyway?. The I.O. signature piece is "Harold".
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