The Upright Citizens Brigade Theatre or UCB Theatre is an improvisational theatre and associated improv and sketch training center with locations in Chelsea, New York, the East Village, New York and Hollywood, California. The theater was founded by Matt Besser, Amy Poehler, Ian Roberts and Matt Walsh, a group of comedians who perform as the Upright Citizens Brigade. The troupe had a show on Comedy Central from 1998 to 2000 and was originally trained by Del Close at Chicago's ImprovOlympic.
Prior to opening their own theatre, the Upright Citizens Brigade performed their signature improv show, ASSSSCAT, first at KGB Bar, and then later at Solo Arts. Solo Arts was the first semi-permanent home to the Upright Citizens Brigade's Harold Teams and is considered by some to be the group's first theatre.
The Upright Citizens Brigade Theatre features a variety of comedy-related acts, including one-person shows, stand-up, and sketch comedy acts, but the theater is best known for its long-form improv shows. Teams that performed the classic Harold improv format, like Mother Mother (Improv), Respecto Montalban, and The Swarm, developed their own forms and helped the Upright Citizens Brigade Theatre become the place for great, cutting-edge comedy.