Joan Mazzonelli and Theatre Building Chicago have been synonymous for nearly a quarter century. She went to work as manager of the theater complex at 1225 W. Belmont in 1985 and was promoted to executive director 11 years ago. During that time TBC’s distinctive missions—to provide venues and support for emerging artists and small theater companies and to develop new musicals—have taken shape and flourished. (The organization’s roots go back to a theater company called the Luther Burbank Dingleberry Festival, founded in 1969; Byron Schaffer Jr. and Ruth Higgins moved it into the Belmont space in 1977.) The place has hosted more than 800 plays, more than a million audience members, and 500 theater companies—including the likes of the Lookingglass, Chicago Shakespeare, and Steppenwolf, which mounted its first Chicago show there in 1979.

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So heads were spinning last week at word that the TBC board, mostly made up of newcomers, had fired Mazzonelli and that TBC’s respected artistic director, John Sparks, would also be leaving. Friday, July 31, will be Mazzonelli’s official last day; Sparks will depart after the Stages festival, which is running August 21-23. This week, in an open letter to the board, TBC cofounder Ruth Higgins questioned the board’s methods, motives, and composition and called for the immediate resignation of all seven members.

The board wants TBC to “leverage” its accomplishments, Wilson explains. The organization “does a lot of really good things, the musical theater workshop is quite unique, and Stages is a really nice product” (though the festival, he says, is “like Brigadoon,” appearing for a single weekend, showcasing six to eight new pieces, and then vanishing until the next year). The problem as he sees it is that TBC has “skewed toward the emerging theater companies,” becoming an informal and unsung long-term partner with them. That’s great, he says, “but that’s not developing any of our artistic programs. Theatre Building Chicago is almost the best-kept secret in town. It’s known among the artistic community, but not well-known within the city.”

According to Mazzonelli, it was “a tough process, and it was quick.” In only three meetings, “all this came to a head.”

To Mazzonelli it looks like the new board doesn’t really get the mission, “the whole idea of the incubator, to provide space and assorted services to up-and-coming troupes, tailor-made from show to show. It’s big and broad, and I think it was difficult for them to understand what it takes to run that program.” A season of fully produced musicals is “a much more tangible kind of project.”